diff --git a/AdvancedCore/src/main/java/com/bencodez/advancedcore/AdvancedCorePlugin.java b/AdvancedCore/src/main/java/com/bencodez/advancedcore/AdvancedCorePlugin.java
index 1bed9a5caf..3b82d9b019 100644
--- a/AdvancedCore/src/main/java/com/bencodez/advancedcore/AdvancedCorePlugin.java
+++ b/AdvancedCore/src/main/java/com/bencodez/advancedcore/AdvancedCorePlugin.java
@@ -1023,8 +1023,10 @@ public void updateReplacements() {
 	 * 
 	 * @param storageType the storage type to load
 	 */
-	@SuppressWarnings("deprecation")
 	public void loadUserAPI(UserStorage storageType) {
+		if (storageType == null) {
+			throw new IllegalArgumentException("User storage must be SQLITE or MYSQL");
+		}
 		if (storageType.equals(UserStorage.SQLITE)) {
 			ArrayList<Column> columns = new ArrayList<>();
 			Column key = new Column("uuid", DataType.STRING);
@@ -1043,8 +1045,6 @@ public void loadUserAPI(UserStorage storageType) {
 						getOptions().getYmlConfig().getData().getConfigurationSection("MySQL")));
 			}
 
-		} else if (storageType.equals(UserStorage.FLAT)) {
-			getLogger().severe("Detected using FLAT storage, this will be removed in the future!");
 		}
 	}
 
diff --git a/AdvancedCore/src/main/java/com/bencodez/advancedcore/api/user/UserData.java b/AdvancedCore/src/main/java/com/bencodez/advancedcore/api/user/UserData.java
index f05924bd98..cf2cc5637b 100644
--- a/AdvancedCore/src/main/java/com/bencodez/advancedcore/api/user/UserData.java
+++ b/AdvancedCore/src/main/java/com/bencodez/advancedcore/api/user/UserData.java
@@ -5,12 +5,9 @@
 import java.util.List;
 import java.util.Map.Entry;
 
-import org.bukkit.configuration.file.FileConfiguration;
-
 import com.bencodez.advancedcore.api.user.usercache.UserDataCache;
 import com.bencodez.advancedcore.api.user.usercache.change.UserDataChangeInt;
 import com.bencodez.advancedcore.api.user.usercache.change.UserDataChangeString;
-import com.bencodez.advancedcore.thread.FileThread;
 import com.bencodez.simpleapi.array.ArrayUtils;
 import com.bencodez.simpleapi.sql.Column;
 import com.bencodez.simpleapi.sql.data.DataValue;
@@ -65,11 +62,6 @@ public boolean getBoolean(String key, boolean useCache, boolean waitForCache) {
 		return getBoolean(key, UserDataFetchMode.fromBooleans(useCache, waitForCache));
 	}
 
-	@Deprecated
-	public FileConfiguration getData(String uuid) {
-		return FileThread.getInstance().getThread().getData(this, uuid);
-	}
-
 	public DataValue getDataValue(String key) {
 		boolean isInt = user.getPlugin().getUserManager().getDataManager().isInt(key);
 		if (isInt) {
@@ -127,15 +119,8 @@ public int getInt(String key, int def, boolean useCache, boolean waitForCache) {
 				UserDataFetchMode.fromBooleans(useCache, waitForCache));
 	}
 
-	@SuppressWarnings("deprecation")
 	public int getInt(UserStorage storage, String key, int def, UserDataFetchMode mode) {
 		if (key == null || key.isEmpty()) {
-			if (storage.equals(UserStorage.FLAT)) {
-				try {
-					return getData(user.getUUID()).getInt(key, def);
-				} catch (Exception ignored) {
-				}
-			}
 			return def;
 		}
 
@@ -241,11 +226,6 @@ public int getInt(UserStorage storage, String key, int def, UserDataFetchMode mo
 					}
 				}
 			}
-		} else if (storage.equals(UserStorage.FLAT)) {
-			try {
-				return getData(user.getUUID()).getInt(key, def);
-			} catch (Exception ignored) {
-			}
 		}
 
 		return def;
@@ -263,12 +243,9 @@ public ArrayList<String> getKeys() {
 		return getKeys(user.getPlugin().getStorageType());
 	}
 
-	@SuppressWarnings("deprecation")
 	public ArrayList<String> getKeys(UserStorage storage) {
 		ArrayList<String> keys = new ArrayList<>();
-		if (storage.equals(UserStorage.FLAT)) {
-			keys = new ArrayList<>(getData(user.getUUID()).getConfigurationSection("").getKeys(false));
-		} else if (storage.equals(UserStorage.MYSQL)) {
+		if (storage.equals(UserStorage.MYSQL)) {
 			List<Column> col = getMySqlRow();
 			if (col != null && !col.isEmpty()) {
 				for (Column c : col) {
@@ -319,7 +296,6 @@ public String getString(String key, UserDataFetchMode mode) {
 		return getString(user.getPlugin().getStorageType(), key, mode);
 	}
 
-	@SuppressWarnings("deprecation")
 	public String getString(UserStorage storage, String key, UserDataFetchMode mode) {
 		if (key == null || key.isEmpty()) {
 			return "";
@@ -388,11 +364,6 @@ public String getString(UserStorage storage, String key, UserDataFetchMode mode)
 					}
 				}
 			}
-		} else if (storage.equals(UserStorage.FLAT)) {
-			try {
-				return getData(user.getUUID()).getString(key, "");
-			} catch (Exception ignored) {
-			}
 		}
 
 		return "";
@@ -454,49 +425,31 @@ public HashMap<String, DataValue> getValues() {
 		return getValues(user.getPlugin().getStorageType());
 	}
 
-	@SuppressWarnings("deprecation")
 	public HashMap<String, DataValue> getValues(UserStorage storage) {
 		if (storage.equals(UserStorage.MYSQL)) {
 			return convert(getMySqlRow());
 		}
 		if (storage.equals(UserStorage.SQLITE)) {
 			return convert(getSQLiteRow());
-		} else if (storage.equals(UserStorage.FLAT)) {
-			HashMap<String, DataValue> list = new HashMap<>();
-			FileConfiguration data = getData(user.getUUID());
-			for (String str : data.getKeys(false)) {
-				if (data.isInt(str)) {
-					list.put(str, new DataValueInt(data.getInt(str)));
-				} else {
-					list.put(str, new DataValueString(data.getString(str, "")));
-				}
-			}
-			return list;
 		}
 		return null;
 	}
 
-	@SuppressWarnings("deprecation")
 	public boolean hasData() {
 		if (user.getPlugin().getStorageType().equals(UserStorage.MYSQL)) {
 			return user.getPlugin().getMysql().containsKey(user.getUUID());
 		}
 		if (user.getPlugin().getStorageType().equals(UserStorage.SQLITE)) {
 			return user.getPlugin().getSQLiteUserTable().containsKey(user.getUUID());
-		} else if (user.getPlugin().getStorageType().equals(UserStorage.FLAT)) {
-			return FileThread.getInstance().getThread().hasPlayerFile(user.getUUID());
 		}
 		return false;
 	}
 
-	@SuppressWarnings("deprecation")
 	public void remove() {
 		if (user.getPlugin().getStorageType().equals(UserStorage.MYSQL)) {
 			user.getPlugin().getMysql().deletePlayer(user.getUUID());
 		} else if (user.getPlugin().getStorageType().equals(UserStorage.SQLITE)) {
 			user.getPlugin().getSQLiteUserTable().delete(new Column("uuid", new DataValueString(user.getUUID())));
-		} else if (user.getPlugin().getStorageType().equals(UserStorage.FLAT)) {
-			FileThread.getInstance().getThread().deletePlayerFile(user.getUUID());
 		}
 		user.clearCache();
 	}
@@ -509,11 +462,6 @@ public void setBoolean(String key, boolean value, boolean queue) {
 		setString(key, "" + value, queue);
 	}
 
-	@Deprecated
-	private void setData(final String uuid, final String path, final Object value) {
-		FileThread.getInstance().getThread().setData(this, uuid, path, value);
-	}
-
 	public void setInt(final String key, final int value) {
 		setInt(key, value, true);
 	}
@@ -530,7 +478,6 @@ public void setInt(UserStorage storage, final String key, final int value, boole
 		setInt(storage, key, value, queue, false);
 	}
 
-	@SuppressWarnings("deprecation")
 	public void setInt(final UserStorage storage, final String key, final int value, boolean queue, boolean async) {
 		if (key.equals("")) {
 			user.getPlugin().debug("No key: " + key + " to " + value);
@@ -565,8 +512,6 @@ public void run() {
 						user.getPlugin().getSQLiteUserTable().update(primary, columns);
 					} else if (storage.equals(UserStorage.MYSQL)) {
 						user.getPlugin().getMysql().update(user.getUUID(), key, new DataValueInt(value));
-					} else if (storage.equals(UserStorage.FLAT)) {
-						setData(user.getUUID(), key, value);
 					}
 
 					if (!user.isCached()) {
@@ -585,8 +530,6 @@ public void run() {
 				user.getPlugin().getSQLiteUserTable().update(primary, columns);
 			} else if (storage.equals(UserStorage.MYSQL)) {
 				user.getPlugin().getMysql().update(user.getUUID(), key, new DataValueInt(value));
-			} else if (storage.equals(UserStorage.FLAT)) {
-				setData(user.getUUID(), key, value);
 			}
 
 			if (!user.isCached()) {
@@ -611,7 +554,6 @@ public void setString(UserStorage storage, final String key, final String value,
 		setString(storage, key, value, queue, false);
 	}
 
-	@SuppressWarnings("deprecation")
 	public void setString(final UserStorage storage, final String key, final String value, boolean queue,
 			boolean async) {
 		if (key.equals("") && value != null) {
@@ -647,8 +589,6 @@ public void run() {
 						user.getPlugin().getSQLiteUserTable().update(primary, columns);
 					} else if (storage.equals(UserStorage.MYSQL)) {
 						user.getPlugin().getMysql().update(user.getUUID(), key, new DataValueString(value));
-					} else if (storage.equals(UserStorage.FLAT)) {
-						setData(user.getUUID(), key, value);
 					}
 					if (!user.isCached()) {
 						user.getPlugin().getUserManager().onChange(user, key);
@@ -665,8 +605,6 @@ public void run() {
 				user.getPlugin().getSQLiteUserTable().update(primary, columns);
 			} else if (storage.equals(UserStorage.MYSQL)) {
 				user.getPlugin().getMysql().update(user.getUUID(), key, new DataValueString(value));
-			} else if (storage.equals(UserStorage.FLAT)) {
-				setData(user.getUUID(), key, value);
 			}
 			if (!user.isCached()) {
 				user.getPlugin().getUserManager().onChange(user, key);
@@ -700,7 +638,6 @@ public void setValues(String key, DataValue value) {
 		setValues(user.getPlugin().getStorageType(), values);
 	}
 
-	@SuppressWarnings("deprecation")
 	public void setValues(UserStorage storage, HashMap<String, DataValue> values) {
 		if (storage.equals(UserStorage.MYSQL)) {
 			if (user.getPlugin().getMysql() != null) {
@@ -721,14 +658,6 @@ public void setValues(UserStorage storage, HashMap<String, DataValue> values) {
 				user.getPlugin().getSQLiteUserTable().update(new Column("uuid", new DataValueString(user.getUUID())),
 						cols);
 			}
-		} else if (storage.equals(UserStorage.FLAT)) {
-			for (Entry<String, DataValue> entry : values.entrySet()) {
-				if (entry.getValue() instanceof DataValueString) {
-					setData(user.getUUID(), entry.getKey(), entry.getValue().getString());
-				} else if (entry.getValue() instanceof DataValueInt) {
-					setData(user.getUUID(), entry.getKey(), entry.getValue().getInt());
-				}
-			}
 		}
 	}
 
diff --git a/AdvancedCore/src/main/java/com/bencodez/advancedcore/api/user/UserManager.java b/AdvancedCore/src/main/java/com/bencodez/advancedcore/api/user/UserManager.java
index edb608a9a9..28007d0809 100644
--- a/AdvancedCore/src/main/java/com/bencodez/advancedcore/api/user/UserManager.java
+++ b/AdvancedCore/src/main/java/com/bencodez/advancedcore/api/user/UserManager.java
@@ -1,6 +1,5 @@
 package com.bencodez.advancedcore.api.user;
 
-import java.io.File;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.List;
@@ -20,7 +19,6 @@
 import com.bencodez.simpleapi.array.ArrayUtils;
 import com.bencodez.simpleapi.sql.Column;
 import com.bencodez.simpleapi.sql.DataType;
-import com.bencodez.simpleapi.sql.data.DataValue;
 import com.bencodez.simpleapi.sql.data.DataValueString;
 
 import lombok.Getter;
@@ -49,23 +47,14 @@ public UserManager(AdvancedCorePlugin plugin) {
 		load();
 	}
 
-	@SuppressWarnings("deprecation")
 	public void copyColumnData(String columnFromName, String columnToName) {
 		if (plugin.getStorageType().equals(UserStorage.MYSQL)) {
 			plugin.getMysql().copyColumnData(columnFromName, columnToName, DataType.STRING);
 		} else if (plugin.getStorageType().equals(UserStorage.SQLITE)) {
 			plugin.getSQLiteUserTable().copyColumnData(columnFromName, columnToName, DataType.STRING);
-		} else if (plugin.getStorageType().equals(UserStorage.FLAT)) {
-			for (String uuid : getAllUUIDs()) {
-				AdvancedCoreUser user = getUser(UUID.fromString(uuid));
-				user.userDataFetechMode(UserDataFetchMode.NO_CACHE);
-				DataValue data = user.getData().getDataValue(columnFromName);
-				user.getData().setValues(columnToName, data);
-			}
 		}
 	}
 
-	@SuppressWarnings("deprecation")
 	public List<String> getAllColumns() {
 		UserStorage storage = plugin.getStorageType();
 		if (storage.equals(UserStorage.SQLITE)) {
@@ -73,14 +62,8 @@ public List<String> getAllColumns() {
 		}
 		if (storage.equals(UserStorage.MYSQL)) {
 			return plugin.getMysql().getColumns();
-		} else {
-			AdvancedCoreUser user = getRandomUser();
-			if (user == null) {
-				return new ArrayList<>();
-			}
-			user.userDataFetechMode(UserDataFetchMode.NO_CACHE);
-			return new ArrayList<>(user.getData().getData(user.getUUID()).getConfigurationSection("").getKeys(false));
 		}
+		return new ArrayList<>();
 	}
 
 	@Deprecated
@@ -94,34 +77,14 @@ public HashMap<UUID, ArrayList<Column>> getAllKeys(UserStorage storage) {
 		}
 		if (storage.equals(UserStorage.MYSQL)) {
 			return plugin.getMysql().getAllQuery();
-		} else {
-			HashMap<UUID, ArrayList<Column>> cols = new HashMap<>();
-			for (String uuid : getAllUUIDs()) {
-				AdvancedCoreUser user = getUser(UUID.fromString(uuid));
-				user.userDataFetechMode(UserDataFetchMode.NO_CACHE);
-				ArrayList<Column> col = new ArrayList<>();
-				for (Entry<String, DataValue> entry : user.getData().getValues().entrySet()) {
-					col.add(new Column(entry.getKey(), entry.getValue()));
-				}
-				cols.put(UUID.fromString(uuid), col);
-			}
-			return cols;
 		}
+		return new HashMap<>();
 	}
 
-	@SuppressWarnings("deprecation")
 	public ArrayList<String> getAllPlayerNames() {
 		if (plugin.isLoadUserData()) {
 			ArrayList<String> names = new ArrayList<>();
-			if (AdvancedCorePlugin.getInstance().getStorageType().equals(UserStorage.FLAT)) {
-				for (String uuid : getAllUUIDs()) {
-					AdvancedCoreUser user = getUser(UUID.fromString(uuid));
-					String name = user.getPlayerName();
-					if (name != null && !name.isEmpty() && !name.equalsIgnoreCase("Error getting name")) {
-						names.add(name);
-					}
-				}
-			} else if (AdvancedCorePlugin.getInstance().getStorageType().equals(UserStorage.SQLITE)) {
+			if (AdvancedCorePlugin.getInstance().getStorageType().equals(UserStorage.SQLITE)) {
 				ArrayList<String> data = plugin.getSQLiteUserTable().getNames();
 				for (String name : data) {
 					if (name != null && !name.isEmpty() && !name.equalsIgnoreCase("Error getting name")) {
@@ -145,13 +108,11 @@ public ArrayList<String> getAllPlayerNames() {
 	 * Storage-agnostic streaming iteration over all users + their column data.
 	 *
 	 * MYSQL: uses plugin.getMysql().forEachUser(...) SQLITE: uses
-	 * plugin.getSQLiteUserTable().forEachUser(...) FLAT: iterates UUID files and
-	 * builds columns per user (no giant map).
+	 * plugin.getSQLiteUserTable().forEachUser(...).
 	 * 
 	 * @param perUser    BiConsumer called per user with UUID and column list
 	 * @param onFinished Consumer called once after all users processed with total
 	 */
-	@SuppressWarnings("deprecation")
 	public void forEachUserKeys(BiConsumer<UUID, ArrayList<Column>> perUser, Consumer<Integer> onFinished) {
 		UserStorage storage = plugin.getStorageType();
 
@@ -173,60 +134,15 @@ public void forEachUserKeys(BiConsumer<UUID, ArrayList<Column>> perUser, Consume
 			return;
 		}
 
-		// FLAT fallback (stream-like; no giant HashMap)
-		int processed = 0;
-		try {
-			for (String uuidStr : getAllUUIDs(UserStorage.FLAT)) {
-				if (uuidStr == null || uuidStr.isEmpty() || "null".equalsIgnoreCase(uuidStr)) {
-					continue;
-				}
-
-				UUID uuid;
-				try {
-					uuid = UUID.fromString(uuidStr);
-				} catch (IllegalArgumentException ignored) {
-					continue;
-				}
-
-				AdvancedCoreUser user = getUser(uuid);
-				user.userDataFetechMode(UserDataFetchMode.NO_CACHE);
-
-				ArrayList<Column> colList = new ArrayList<>();
-				for (Entry<String, DataValue> entry : user.getData().getValues().entrySet()) {
-					colList.add(new Column(entry.getKey(), entry.getValue()));
-				}
-
-				processed++;
-				perUser.accept(uuid, colList);
-			}
-		} finally {
-			if (onFinished != null) {
-				onFinished.accept(processed);
-			}
-		}
+		throw new IllegalStateException("User storage is not configured");
 	}
 
 	public ArrayList<String> getAllUUIDs() {
 		return ArrayUtils.removeDuplicates(getAllUUIDs(plugin.getStorageType()));
 	}
 
-	@SuppressWarnings("deprecation")
 	public ArrayList<String> getAllUUIDs(UserStorage storage) {
 		if (plugin.isLoadUserData()) {
-			if (storage.equals(UserStorage.FLAT)) {
-				File folder = new File(plugin.getDataFolder() + File.separator + "Data");
-				String[] fileNames = folder.list();
-				ArrayList<String> uuids = new ArrayList<>();
-				if (fileNames != null) {
-					for (String playerFile : fileNames) {
-						if (!playerFile.equals("null") && !playerFile.equals("")) {
-							String uuid = playerFile.replace(".yml", "");
-							uuids.add(uuid);
-						}
-					}
-				}
-				return uuids;
-			}
 			if (storage.equals(UserStorage.SQLITE)) {
 				List<Column> cols = plugin.getSQLiteUserTable().getRows();
 				ArrayList<String> uuids = new ArrayList<>();
@@ -253,22 +169,12 @@ public ArrayList<String> getAllUUIDs(UserStorage storage) {
 		return new ArrayList<>();
 	}
 
-	@SuppressWarnings("deprecation")
 	public ArrayList<Integer> getNumbersInColumn(String columnName) {
 		if (plugin.getStorageType().equals(UserStorage.MYSQL)) {
 			return plugin.getMysql().getNumbersInColumn(columnName);
 		}
 		if (plugin.getStorageType().equals(UserStorage.SQLITE)) {
 			return plugin.getSQLiteUserTable().getNumbersInColumn(columnName);
-		} else if (plugin.getStorageType().equals(UserStorage.FLAT)) {
-			ArrayList<Integer> nums = new ArrayList<>();
-			for (String uuid : getAllUUIDs()) {
-				AdvancedCoreUser user = getUser(UUID.fromString(uuid));
-				user.userDataFetechMode(UserDataFetchMode.NO_CACHE);
-				int num = user.getData().getInt(columnName, 0, true, true);
-				nums.add(num);
-			}
-			return nums;
 		}
 		return new ArrayList<>();
 	}
@@ -462,21 +368,6 @@ public void removeAllKeyValues(String key, DataType type) {
 			plugin.getSQLiteUserTable().wipeColumnData(key, type);
 		} else if (plugin.getStorageType().equals(UserStorage.MYSQL)) {
 			plugin.getMysql().wipeColumnData(key, type);
-		} else {
-			for (String uuid : getAllUUIDs()) {
-				AdvancedCoreUser user = getUser(UUID.fromString(uuid));
-				user.userDataFetechMode(UserDataFetchMode.NO_CACHE);
-				switch (type) {
-				case INTEGER:
-					user.getData().setInt(key, 0);
-					break;
-				case STRING:
-					user.getData().setString(key, "");
-					break;
-				default:
-					break;
-				}
-			}
 		}
 	}
 
diff --git a/AdvancedCore/src/main/java/com/bencodez/advancedcore/api/user/UserStorage.java b/AdvancedCore/src/main/java/com/bencodez/advancedcore/api/user/UserStorage.java
index 6e062a37f8..aae6e9ea0f 100644
--- a/AdvancedCore/src/main/java/com/bencodez/advancedcore/api/user/UserStorage.java
+++ b/AdvancedCore/src/main/java/com/bencodez/advancedcore/api/user/UserStorage.java
@@ -2,13 +2,13 @@
 
 public enum UserStorage {
 
-	MYSQL, SQLITE, @Deprecated
-	FLAT;
+	MYSQL, SQLITE;
 
 	public static UserStorage value(String str) {
-		// if (str.equalsIgnoreCase("FLAT")) {
-		// return SQLITE;
-		// }
+		if (str != null && "FLAT".equalsIgnoreCase(str.trim())) {
+			throw new IllegalArgumentException("FLAT user storage has been removed. Convert existing data to "
+					+ "SQLITE or MYSQL using the previous version before upgrading; existing Data files are not modified.");
+		}
 		for (UserStorage s : values()) {
 			if (s.toString().equalsIgnoreCase(str)) {
 				return s;
diff --git a/AdvancedCore/src/main/java/com/bencodez/advancedcore/thread/FileThread.java b/AdvancedCore/src/main/java/com/bencodez/advancedcore/thread/FileThread.java
index cd99a21afe..7043b87930 100644
--- a/AdvancedCore/src/main/java/com/bencodez/advancedcore/thread/FileThread.java
+++ b/AdvancedCore/src/main/java/com/bencodez/advancedcore/thread/FileThread.java
@@ -1,13 +1,6 @@
 package com.bencodez.advancedcore.thread;
 
-import java.io.File;
-
-import org.bukkit.configuration.file.FileConfiguration;
-import org.bukkit.configuration.file.YamlConfiguration;
-
 import com.bencodez.advancedcore.AdvancedCorePlugin;
-import com.bencodez.advancedcore.api.misc.files.FilesManager;
-import com.bencodez.advancedcore.api.user.UserData;
 
 /**
  * The Class Thread.
@@ -19,100 +12,6 @@ public class FileThread {
 	 */
 	public class ReadThread extends java.lang.Thread {
 
-		/**
-		 * Deletes a player file.
-		 *
-		 * @param uuid the player UUID
-		 */
-		@Deprecated
-		public void deletePlayerFile(String uuid) {
-			synchronized (FileThread.getInstance()) {
-				try {
-					File dFile = new File(AdvancedCorePlugin.getInstance().getDataFolder() + File.separator + "Data",
-							uuid + ".yml");
-					if (dFile.exists()) {
-						dFile.delete();
-					}
-
-				} catch (Exception e) {
-					AdvancedCorePlugin.getInstance().debug(e);
-				}
-			}
-		}
-
-		/**
-		 * Gets data for a player.
-		 *
-		 * @param userData the user data
-		 * @param uuid the player UUID
-		 * @return the file configuration
-		 */
-		@Deprecated
-		public FileConfiguration getData(UserData userData, String uuid) {
-			synchronized (FileThread.getInstance()) {
-				try {
-					File dFile = getPlayerFile(uuid);
-					if (dFile != null) {
-						FileConfiguration data = YamlConfiguration.loadConfiguration(dFile);
-						return data;
-					}
-				} catch (Exception e) {
-					AdvancedCorePlugin.getInstance().debug(e);
-				}
-				AdvancedCorePlugin.getInstance().getLogger()
-						.warning("Filed to load " + uuid + ".yml, turn debug on to see full stacktraces");
-				return null;
-			}
-
-		}
-
-		/**
-		 * Gets the player file.
-		 *
-		 * @param uuid the player UUID
-		 * @return the file
-		 */
-		@Deprecated
-		public File getPlayerFile(String uuid) {
-			synchronized (FileThread.getInstance()) {
-				try {
-					File dFile = new File(AdvancedCorePlugin.getInstance().getDataFolder() + File.separator + "Data",
-							uuid + ".yml");
-					FileConfiguration data = YamlConfiguration.loadConfiguration(dFile);
-					if (!dFile.exists()) {
-						FilesManager.getInstance().editFile(dFile, data);
-					}
-					return dFile;
-				} catch (Exception e) {
-					AdvancedCorePlugin.getInstance().debug(e);
-				}
-				AdvancedCorePlugin.getInstance().getLogger()
-						.warning("Failed to load " + uuid + ".yml, turn debug on to see full stacktraces");
-				return null;
-			}
-		}
-
-		/**
-		 * Checks if a player file exists.
-		 *
-		 * @param uuid the player UUID
-		 * @return true if file exists
-		 */
-		@Deprecated
-		public boolean hasPlayerFile(String uuid) {
-			synchronized (FileThread.getInstance()) {
-				try {
-					File dFile = new File(AdvancedCorePlugin.getInstance().getDataFolder() + File.separator + "Data",
-							uuid + ".yml");
-					return dFile.exists();
-
-				} catch (Exception e) {
-					AdvancedCorePlugin.getInstance().debug(e);
-				}
-				return false;
-			}
-		}
-
 		@Override
 		public void run() {
 			while (!isInterrupted()) {
@@ -136,31 +35,6 @@ public void run(Runnable run) {
 			}
 
 		}
-
-		/**
-		 * Sets data for a player.
-		 *
-		 * @param userData the user data
-		 * @param uuid the player UUID
-		 * @param path the data path
-		 * @param value the value to set
-		 */
-		@Deprecated
-		public void setData(UserData userData, final String uuid, final String path, final Object value) {
-			synchronized (FileThread.getInstance()) {
-				try {
-					File dFile = getPlayerFile(uuid);
-					FileConfiguration data = getData(userData, uuid);
-					data.set(path, value);
-					data.save(dFile);
-				} catch (Exception e) {
-					AdvancedCorePlugin.getInstance().getLogger().warning(
-							"Failed to set a value for " + uuid + ".yml, turn debug on to see full stacktraces");
-					AdvancedCorePlugin.getInstance().debug(e);
-				}
-			}
-
-		}
 	}
 
 	/** The instance. */
diff --git a/AdvancedCore/src/test/java/com/bencodez/advancedcore/tests/user/SqlOnlyUserDataTest.java b/AdvancedCore/src/test/java/com/bencodez/advancedcore/tests/user/SqlOnlyUserDataTest.java
new file mode 100644
index 0000000000..9603099187
--- /dev/null
+++ b/AdvancedCore/src/test/java/com/bencodez/advancedcore/tests/user/SqlOnlyUserDataTest.java
@@ -0,0 +1,115 @@
+package com.bencodez.advancedcore.tests.user;
+
+import static org.junit.jupiter.api.Assertions.*;
+import static org.mockito.ArgumentMatchers.*;
+import static org.mockito.Mockito.*;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.UUID;
+
+import org.junit.jupiter.api.Test;
+import org.mockito.ArgumentCaptor;
+
+import com.bencodez.advancedcore.AdvancedCorePlugin;
+import com.bencodez.advancedcore.api.user.AdvancedCoreUser;
+import com.bencodez.advancedcore.api.user.UserData;
+import com.bencodez.advancedcore.api.user.UserDataFetchMode;
+import com.bencodez.advancedcore.api.user.UserManager;
+import com.bencodez.advancedcore.api.user.UserStorage;
+import com.bencodez.advancedcore.api.user.userstorage.mysql.MySQL;
+import com.bencodez.advancedcore.api.user.userstorage.sql.UserTable;
+import com.bencodez.simpleapi.sql.Column;
+import com.bencodez.simpleapi.sql.data.DataValue;
+import com.bencodez.simpleapi.sql.data.DataValueInt;
+import com.bencodez.simpleapi.sql.data.DataValueString;
+
+class SqlOnlyUserDataTest {
+    @Test
+    void bothSqlBackendsRetainReadAndExistenceBehavior() {
+        for (UserStorage storage : UserStorage.values()) {
+            Fixture fixture = new Fixture(storage);
+            ArrayList<Column> row = new ArrayList<>(List.of(new Column("Points", new DataValueInt(12)),
+                    new Column("PlayerName", new DataValueString("Ben"))));
+            when(fixture.mysql.getExact(fixture.id)).thenReturn(row);
+            when(fixture.sqlite.getExact(any(Column.class))).thenReturn(row);
+            when(fixture.mysql.containsKey(fixture.id)).thenReturn(true);
+            when(fixture.sqlite.containsKey(fixture.id)).thenReturn(true);
+            assertEquals(12, fixture.data.getInt("Points", 0, UserDataFetchMode.NO_CACHE));
+            assertEquals("Ben", fixture.data.getString("PlayerName", UserDataFetchMode.NO_CACHE));
+            assertEquals(List.of("Points", "PlayerName"), fixture.data.getKeys());
+            assertEquals(2, fixture.data.getValues().size());
+            assertTrue(fixture.data.hasData());
+            verify(fixture.plugin, never()).getDataFolder();
+        }
+    }
+
+    @Test
+    void scalarWritesKeepUuidAndSqlValueTypes() {
+        Fixture sqlite = new Fixture(UserStorage.SQLITE);
+        sqlite.data.setInt("Points", 24, false);
+        sqlite.data.setString("PlayerName", "Ben", false);
+        ArgumentCaptor<Column> key = ArgumentCaptor.forClass(Column.class);
+        @SuppressWarnings({ "rawtypes", "unchecked" })
+        ArgumentCaptor<ArrayList<Column>> rows = ArgumentCaptor.forClass((Class) ArrayList.class);
+        verify(sqlite.sqlite, times(2)).update(key.capture(), rows.capture());
+        assertEquals(sqlite.id, key.getValue().getValue().getString());
+        assertEquals("uuid", rows.getAllValues().get(0).get(0).getName());
+        assertEquals(24, rows.getAllValues().get(0).get(1).getValue().getInt());
+        assertEquals("Ben", rows.getAllValues().get(1).get(1).getValue().getString());
+        verify(sqlite.manager).onChange(sqlite.user, "Points");
+        verify(sqlite.manager).onChange(sqlite.user, "PlayerName");
+
+        Fixture mysql = new Fixture(UserStorage.MYSQL);
+        mysql.data.setInt("Points", 24, false);
+        mysql.data.setString("PlayerName", "Ben", false);
+        ArgumentCaptor<DataValue> values = ArgumentCaptor.forClass(DataValue.class);
+        verify(mysql.mysql).update(eq(mysql.id), eq("Points"), values.capture());
+        assertEquals(24, values.getValue().getInt());
+        verify(mysql.mysql).update(eq(mysql.id), eq("PlayerName"), values.capture());
+        assertEquals("Ben", values.getValue().getString());
+        verify(mysql.plugin, never()).getDataFolder();
+        verify(sqlite.plugin, never()).getDataFolder();
+    }
+
+    @Test
+    void removalUsesSelectedSqlTableThenClearsExistingUserCache() {
+        for (UserStorage storage : UserStorage.values()) {
+            Fixture fixture = new Fixture(storage);
+            fixture.data.remove();
+            if (storage == UserStorage.MYSQL) {
+                var order = inOrder(fixture.mysql, fixture.user);
+                order.verify(fixture.mysql).deletePlayer(fixture.id);
+                order.verify(fixture.user).clearCache();
+            } else {
+                ArgumentCaptor<Column> key = ArgumentCaptor.forClass(Column.class);
+                var order = inOrder(fixture.sqlite, fixture.user);
+                order.verify(fixture.sqlite).delete(key.capture());
+                order.verify(fixture.user).clearCache();
+                assertEquals("uuid", key.getValue().getName());
+                assertEquals(fixture.id, key.getValue().getValue().getString());
+            }
+            verify(fixture.plugin, never()).getDataFolder();
+        }
+    }
+
+    private static final class Fixture {
+        final String id = UUID.randomUUID().toString();
+        final AdvancedCorePlugin plugin = mock(AdvancedCorePlugin.class);
+        final AdvancedCoreUser user = mock(AdvancedCoreUser.class);
+        final MySQL mysql = mock(MySQL.class);
+        final UserTable sqlite = mock(UserTable.class);
+        final UserManager manager = mock(UserManager.class);
+        final UserData data = new UserData(user);
+
+        Fixture(UserStorage storage) {
+            when(user.getPlugin()).thenReturn(plugin);
+            when(user.getUUID()).thenReturn(id);
+            when(user.getPlayerName()).thenReturn("Ben");
+            when(plugin.getStorageType()).thenReturn(storage);
+            when(plugin.getMysql()).thenReturn(mysql);
+            when(plugin.getSQLiteUserTable()).thenReturn(sqlite);
+            when(plugin.getUserManager()).thenReturn(manager);
+        }
+    }
+}
diff --git a/AdvancedCore/src/test/java/com/bencodez/advancedcore/tests/user/UserStorageTest.java b/AdvancedCore/src/test/java/com/bencodez/advancedcore/tests/user/UserStorageTest.java
index 79017c79d1..76e730bd28 100644
--- a/AdvancedCore/src/test/java/com/bencodez/advancedcore/tests/user/UserStorageTest.java
+++ b/AdvancedCore/src/test/java/com/bencodez/advancedcore/tests/user/UserStorageTest.java
@@ -15,7 +15,6 @@ public class UserStorageTest {
 	public void testValue_caseInsensitiveMatches() {
 		assertEquals(UserStorage.MYSQL, UserStorage.value("mysql"));
 		assertEquals(UserStorage.SQLITE, UserStorage.value("SQLITE"));
-		assertEquals(UserStorage.FLAT, UserStorage.value("flat"));
 	}
 
 	@Test
@@ -24,4 +23,18 @@ public void testValue_unknownReturnsNull() {
 		assertNull(UserStorage.value(""));
 		assertNull(UserStorage.value("   "));
 	}
+
+	@Test
+	public void flatIsNotAnAvailableStorageType() {
+		assertArrayEquals(new UserStorage[] { UserStorage.MYSQL, UserStorage.SQLITE }, UserStorage.values());
+		assertThrows(IllegalArgumentException.class, () -> UserStorage.valueOf("FLAT"));
+	}
+
+	@Test
+	public void retiredFlatConfigurationFailsRatherThanSelectingAnEmptySqlDatabase() {
+		for (String value : new String[] { "FLAT", "flat", "Flat", " FLAT " }) {
+			IllegalArgumentException failure = assertThrows(IllegalArgumentException.class, () -> UserStorage.value(value));
+			assertTrue(failure.getMessage().contains("previous version"));
+		}
+	}
 }
diff --git a/docs/sql-only-user-storage.md b/docs/sql-only-user-storage.md
new file mode 100644
index 0000000000..c730fad214
--- /dev/null
+++ b/docs/sql-only-user-storage.md
@@ -0,0 +1,24 @@
+# SQL-only user storage
+
+User storage now supports `SQLITE` and `MYSQL` only. `FLAT` is removed from the
+enum, normal reads/writes, enumeration, column operations, startup, and deprecated
+per-player file helpers. Existing `Data/*.yml` files are neither deleted nor
+converted by this change. Ordinary YAML configuration and generic file utilities
+remain available.
+
+An explicit `DataStorage: FLAT` setting fails with an explanatory error instead
+of silently starting with an empty SQL database. Complete conversion with the
+existing conversion commands in the previous version before upgrading, then
+select the populated `SQLITE` or `MYSQL` backend. No new migration, automatic
+storage switch, schema change, or rewrite of the existing SQL converter is added.
+SQL-to-SQL conversion remains available through `convertDataStorage`.
+
+This deliberately removes the deprecated `UserStorage.FLAT` enum constant,
+`UserData.getData(String)`, and the per-player file CRUD methods on
+`FileThread.ReadThread`. Integrations still calling those FLAT-only APIs must
+migrate before upgrading. SQL-facing public APIs, fetch modes, cached changes,
+write scheduling, serialized values, and reward queues are unchanged.
+
+The follow-up SQL abstraction builds on this removal. Coordinate both branches
+with changes to user data/cache code in PR #317; this removal does not merge or
+modify that PR. SimpleAPI remains `1.0.2-SNAPSHOT` in the single Maven project.