diff --git a/game/src/main/java/org/toop/game/BitboardGame.java b/game/src/main/java/org/toop/game/BitboardGame.java
new file mode 100644
index 0000000..a0a3b69
--- /dev/null
+++ b/game/src/main/java/org/toop/game/BitboardGame.java
@@ -0,0 +1,71 @@
+package org.toop.game;
+
+import org.toop.framework.gameFramework.GameState;
+
+import java.util.Arrays;
+
+public abstract class BitboardGame {
+	private final int columnSize;
+	private final int rowSize;
+
+	// long is 64 bits. Every game has a limit of 64 cells maximum.
+	private final long[] playerBitboard;
+	private int currentTurn;
+
+	public BitboardGame(int columnSize, int rowSize, int playerCount) {
+		this.columnSize = columnSize;
+		this.rowSize = rowSize;
+
+		this.playerBitboard = new long[playerCount];
+		this.currentTurn = 0;
+
+		Arrays.fill(playerBitboard, 0L);
+	}
+
+	public BitboardGame(BitboardGame other) {
+		this.columnSize = other.columnSize;
+		this.rowSize = other.rowSize;
+
+		this.playerBitboard = Arrays.copyOf(other.playerBitboard, other.playerBitboard.length);
+		this.currentTurn = other.currentTurn;
+	}
+
+	public int getColumnSize() {
+		return this.columnSize;
+	}
+
+	public int getRowSize() {
+		return this.rowSize;
+	}
+
+	public long getPlayerBitboard(int player) {
+		return this.playerBitboard[player];
+	}
+
+	public void setPlayerBitboard(int player, long bitboard) {
+		this.playerBitboard[player] = bitboard;
+	}
+
+	public int getPlayerCount() {
+		return playerBitboard.length;
+	}
+
+	public int getCurrentTurn() {
+		return currentTurn;
+	}
+
+	public int getCurrentPlayer() {
+		return currentTurn % playerBitboard.length;
+	}
+
+	public int getNextPlayer() {
+		return (currentTurn + 1) % playerBitboard.length;
+	}
+
+	public void nextTurn() {
+		currentTurn++;
+	}
+
+	public abstract long getLegalMoves();
+	public abstract GameState play(long move);
+}
\ No newline at end of file
diff --git a/game/src/main/java/org/toop/game/reversi/BitboardReversi.java b/game/src/main/java/org/toop/game/reversi/BitboardReversi.java
new file mode 100644
index 0000000..381a9c5
--- /dev/null
+++ b/game/src/main/java/org/toop/game/reversi/BitboardReversi.java
@@ -0,0 +1,137 @@
+package org.toop.game.reversi;
+
+import org.toop.framework.gameFramework.GameState;
+import org.toop.game.BitboardGame;
+
+public class BitboardReversi extends BitboardGame {
+	public record Score(int black, int white) {}
+
+	private final long notAFile = 0xfefefefefefefefeL;
+	private final long notHFile = 0x7f7f7f7f7f7f7f7fL;
+
+	public BitboardReversi() {
+		super(8, 8, 2);
+
+		// Black (player 0)
+		setPlayerBitboard(0, (1L << (3 + 4 * 8)) | (1L << (4 + 3 * 8)));
+
+		// White (player 1)
+		setPlayerBitboard(1, (1L << (3 + 3 * 8)) | (1L << (4 + 4 * 8)));	}
+
+	@Override
+	public long getLegalMoves() {
+		final long player = getPlayerBitboard(getCurrentPlayer());
+		final long opponent = getPlayerBitboard(getNextPlayer());
+
+		long legalMoves = 0L;
+		legalMoves |= computeMoves(player, opponent, 8, -1L);
+		legalMoves |= computeMoves(player, opponent, -8, -1L);
+		legalMoves |= computeMoves(player, opponent, 1, notAFile);
+		legalMoves |= computeMoves(player, opponent, -1, notHFile);
+		legalMoves |= computeMoves(player, opponent, 9, notAFile);
+		legalMoves |= computeMoves(player, opponent, 7, notHFile);
+		legalMoves |= computeMoves(player, opponent, -7, notHFile);
+		legalMoves |= computeMoves(player, opponent, -9, notAFile);
+
+		return legalMoves;
+	}
+
+	public long getFlips(long move) {
+		final long player = getPlayerBitboard(getCurrentPlayer());
+		final long opponent = getPlayerBitboard(getNextPlayer());
+
+		long flips = 0L;
+		flips |= computeFlips(move, player, opponent, 8, -1L);
+		flips |= computeFlips(move, player, opponent, -8, -1L);
+		flips |= computeFlips(move, player, opponent, 1, notAFile);
+		flips |= computeFlips(move, player, opponent, -1, notHFile);
+		flips |= computeFlips(move, player, opponent, 9, notAFile);
+		flips |= computeFlips(move, player, opponent, 7, notHFile);
+		flips |= computeFlips(move, player, opponent, -7, notHFile);
+		flips |= computeFlips(move, player, opponent, -9, notAFile);
+
+		return flips;
+	}
+
+	@Override
+	public GameState play(long move) {
+		final long flips = getFlips(move);
+
+		long player = getPlayerBitboard(getCurrentPlayer());
+		long opponent = getPlayerBitboard(getNextPlayer());
+
+		player |= move | flips;
+		opponent &= ~flips;
+
+		setPlayerBitboard(getCurrentPlayer(), player);
+		setPlayerBitboard(getNextPlayer(), opponent);
+
+		nextTurn();
+
+		final long nextLegalMoves = getLegalMoves();
+
+		if (nextLegalMoves <= 0) {
+			nextTurn();
+
+			final long skippedLegalMoves = getLegalMoves();
+
+			if (skippedLegalMoves <= 0) {
+				final long black = getPlayerBitboard(0);
+				final long white = getPlayerBitboard(1);
+
+				final int blackCount = Long.bitCount(black);
+				final int whiteCount = Long.bitCount(white);
+
+				if (blackCount == whiteCount) {
+					return GameState.DRAW;
+				}
+
+				return GameState.WIN;
+			}
+
+			return GameState.TURN_SKIPPED;
+		}
+
+		return GameState.NORMAL;
+	}
+
+	public Score getScore() {
+		return new Score(
+			Long.bitCount(getPlayerBitboard(0)),
+			Long.bitCount(getPlayerBitboard(1))
+		);
+	}
+
+	private long computeMoves(long player, long opponent, int shift, long mask) {
+		long moves = player;
+
+		while (true) {
+			if (shift > 0) moves = (moves << shift) & mask;
+			else moves = (moves >>> -shift) & mask;
+
+			long newMoves = moves & opponent;
+			if (newMoves == 0) break;
+			moves = newMoves;
+		}
+
+		if (shift > 0) moves = (moves << shift) & mask;
+		else moves = (moves >>> -shift) & mask;
+
+		return moves & ~(player | opponent);
+	}
+
+	private long computeFlips(long move, long player, long opponent, int shift, long mask) {
+		long flips = 0L;
+
+		long moves = move;
+
+		while (true) {
+			if (shift > 0) moves = (moves << shift) & mask;
+			else moves = (moves >>> -shift) & mask;
+
+			if ((moves & opponent) != 0) flips |= moves;
+			else if ((moves & player) != 0) return flips;
+			else return 0L;
+		}
+	}
+}
\ No newline at end of file
diff --git a/game/src/main/java/org/toop/game/tictactoe/BitboardTicTacToe.java b/game/src/main/java/org/toop/game/tictactoe/BitboardTicTacToe.java
new file mode 100644
index 0000000..26578f7
--- /dev/null
+++ b/game/src/main/java/org/toop/game/tictactoe/BitboardTicTacToe.java
@@ -0,0 +1,80 @@
+package org.toop.game.tictactoe;
+
+import org.toop.framework.gameFramework.GameState;
+import org.toop.game.BitboardGame;
+
+public class BitboardTicTacToe extends BitboardGame {
+	private final long[] winningLines = {
+		0b111000000L, // top row
+		0b000111000L, // middle row
+		0b000000111L, // bottom row
+		0b100100100L, // left column
+		0b010010010L, // middle column
+		0b001001001L, // right column
+		0b100010001L, // diagonal
+		0b001010100L  // anti-diagonal
+	};
+
+	public BitboardTicTacToe() {
+		super(3, 3, 2);
+	}
+
+	@Override
+	public long getLegalMoves() {
+		final long xBitboard = getPlayerBitboard(0);
+		final long oBitboard = getPlayerBitboard(1);
+
+		final long taken = (xBitboard | oBitboard);
+		return (~taken) & 0x1ffL;
+	}
+
+	@Override
+	public GameState play(long move) {
+		long playerBitboard = getPlayerBitboard(getCurrentPlayer());
+		playerBitboard |= move;
+
+		setPlayerBitboard(getCurrentPlayer(), playerBitboard);
+
+		if (checkWin(playerBitboard)) {
+			return GameState.WIN;
+		}
+
+		if (getLegalMoves() <= 0L || checkEarlyDraw()) {
+			return GameState.DRAW;
+		}
+
+		nextTurn();
+
+		return GameState.NORMAL;
+	}
+
+	private boolean checkWin(long board) {
+		for (final long line : winningLines) {
+			if ((board & line) == line) {
+				return true;
+			}
+		}
+
+		return false;
+	}
+
+	private boolean checkEarlyDraw() {
+		final long xBitboard = getPlayerBitboard(0);
+		final long oBitboard = getPlayerBitboard(1);
+
+		final long taken = (xBitboard | oBitboard);
+		final long empty = (~taken) & 0x1FFL;
+
+		for (final long line : winningLines) {
+			if (((line & xBitboard) != 0 && (line & oBitboard) != 0)) {
+				continue;
+			}
+
+			if ((line & empty) != 0) {
+				return false;
+			}
+		}
+
+		return true;
+	}
+}
\ No newline at end of file