diff --git a/lib/rl/draughts.js b/lib/rl/draughts.js
index e3ad515c..ccbc6767 100644
--- a/lib/rl/draughts.js
+++ b/lib/rl/draughts.js
@@ -16,7 +16,7 @@ export default class DraughtsRLEnvironment extends RLEnvironmentBase {
 
 		this._size = [8, 8]
 
-		this._board = new DraughtsBoard(this._size, this._evaluation)
+		this._board = new DraughtsBoard(this._size)
 
 		this._reward = {
 			win: 1,
@@ -106,16 +106,6 @@ export default class DraughtsRLEnvironment extends RLEnvironmentBase {
 		return s
 	}
 
-	set evaluation(func) {
-		if (func) {
-			this._board._evaluator = this._evaluation = (board, turn) => {
-				return func(this._makeState(board, turn, this._turn))
-			}
-		} else {
-			this._board._evaluator = this._evaluation = null
-		}
-	}
-
 	_makeState(board, agentturn, gameturn) {
 		const s = [gameturn]
 		for (let i = 0; i < this._size[0]; i++) {
@@ -137,7 +127,7 @@ export default class DraughtsRLEnvironment extends RLEnvironmentBase {
 	}
 
 	_state2board(state, turn) {
-		const board = new DraughtsBoard(this._size, this._evaluation)
+		const board = new DraughtsBoard(this._size)
 		const opturn = turn === RED ? WHITE : RED
 		for (let i = 0, p = 1; i < this._size[0]; i++) {
 			for (let j = i % 2 === 0 ? 1 : 0; j < this._size[1]; j += 2, p++) {
@@ -234,8 +224,7 @@ export default class DraughtsRLEnvironment extends RLEnvironmentBase {
 }
 
 class DraughtsBoard {
-	constructor(size, evaluator) {
-		this._evaluator = evaluator
+	constructor(size) {
 		this._size = size
 		this._lines = 3
 
@@ -302,7 +291,7 @@ class DraughtsBoard {
 	}
 
 	copy() {
-		const cp = new DraughtsBoard(this._size, this._evaluator)
+		const cp = new DraughtsBoard(this._size)
 		for (let i = 0; i < this._size[0]; i++) {
 			cp._board[i] = this._board[i].concat()
 		}
@@ -310,9 +299,6 @@ class DraughtsBoard {
 	}
 
 	score(turn) {
-		if (this._evaluator) {
-			return this._evaluator(this, turn)
-		}
 		const count = this.count
 		if (turn === RED) {
 			return count.red + count.redking * 2 - count.white - count.whiteking * 4
diff --git a/lib/rl/gem_puzzle.js b/lib/rl/gem_puzzle.js
index 3e672bbd..486db32f 100644
--- a/lib/rl/gem_puzzle.js
+++ b/lib/rl/gem_puzzle.js
@@ -1,8 +1,7 @@
 import { RLEnvironmentBase } from './base.js'
 
 class GemPuzzleBoard {
-	constructor(size, evaluator) {
-		this._evaluator = evaluator
+	constructor(size) {
 		this._size = size
 
 		this.reset()
@@ -57,7 +56,7 @@ class GemPuzzleBoard {
 	}
 
 	copy() {
-		const cp = new GemPuzzleBoard(this._size, this._evaluator)
+		const cp = new GemPuzzleBoard(this._size)
 		for (let i = 0; i < this._size[0]; i++) {
 			for (let j = 0; j < this._size[1]; j++) {
 				cp._board[i][j] = this._board[i][j]
@@ -67,9 +66,6 @@ class GemPuzzleBoard {
 	}
 
 	score() {
-		if (this._evaluator) {
-			return this._evaluator(this)
-		}
 		let s = 0
 		for (let i = 0; i < this._size[0]; i++) {
 			for (let j = 0; j < this._size[1]; j++) {
@@ -489,7 +485,7 @@ export default class GemPuzzleRLEnvironment extends RLEnvironmentBase {
 
 		this._size = [4, 4]
 
-		this._board = new GemPuzzleBoard(this._size, this._evaluation)
+		this._board = new GemPuzzleBoard(this._size)
 
 		this._reward = {
 			win: 10,
@@ -524,16 +520,6 @@ export default class GemPuzzleRLEnvironment extends RLEnvironmentBase {
 		return s
 	}
 
-	set evaluation(func) {
-		if (func) {
-			this._board._evaluator = this._evaluation = board => {
-				return func(this._makeState(board))
-			}
-		} else {
-			this._board._evaluator = this._evaluation = null
-		}
-	}
-
 	_makeState(board) {
 		const s = []
 		for (let i = 0; i < this._size[0]; i++) {
@@ -546,7 +532,7 @@ export default class GemPuzzleRLEnvironment extends RLEnvironmentBase {
 	}
 
 	_state2board(state) {
-		const board = new GemPuzzleBoard(this._size, this._evaluation)
+		const board = new GemPuzzleBoard(this._size)
 		for (let i = 0, p = 0; i < this._size[0]; i++) {
 			for (let j = 0; j < this._size[1]; j++, p++) {
 				board._board[i][j] = state[p] === -1 ? null : state[p]
diff --git a/lib/rl/gomoku.js b/lib/rl/gomoku.js
index 9b2ead00..d490b89c 100644
--- a/lib/rl/gomoku.js
+++ b/lib/rl/gomoku.js
@@ -13,7 +13,7 @@ export default class GomokuRLEnvironment extends RLEnvironmentBase {
 
 		this._size = [8, 8]
 
-		this._board = new GomokuBoard(this._size, this._evaluation)
+		this._board = new GomokuBoard(this._size)
 
 		this._reward = {
 			win: 1,
@@ -50,16 +50,6 @@ export default class GomokuRLEnvironment extends RLEnvironmentBase {
 		return s
 	}
 
-	set evaluation(func) {
-		if (func) {
-			this._board._evaluator = this._evaluation = (board, turn) => {
-				return func(this._makeState(board, turn, this._turn))
-			}
-		} else {
-			this._board._evaluator = this._evaluation = null
-		}
-	}
-
 	_makeState(board, agentturn, gameturn) {
 		const s = [gameturn]
 		for (let i = 0; i < this._size[0]; i++) {
@@ -72,7 +62,7 @@ export default class GomokuRLEnvironment extends RLEnvironmentBase {
 	}
 
 	_state2board(state, turn) {
-		const board = new GomokuBoard(this._size, this._evaluation)
+		const board = new GomokuBoard(this._size)
 		const opturn = board.nextTurn(turn)
 		for (let i = 0, p = 1; i < this._size[0]; i++) {
 			for (let j = 0; j < this._size[1]; j++, p++) {
@@ -164,8 +154,7 @@ export default class GomokuRLEnvironment extends RLEnvironmentBase {
 }
 
 class GomokuBoard {
-	constructor(size, evaluator) {
-		this._evaluator = evaluator
+	constructor(size) {
 		this._size = size
 		this._a = 5
 		this._count = 0
@@ -215,7 +204,7 @@ class GomokuBoard {
 	}
 
 	copy() {
-		const cp = new GomokuBoard(this._size, this._evaluator)
+		const cp = new GomokuBoard(this._size)
 		for (let i = 0; i < this._size[0]; i++) {
 			for (let j = 0; j < this._size[1]; j++) {
 				cp._board[i][j] = this._board[i][j]
@@ -226,9 +215,6 @@ class GomokuBoard {
 	}
 
 	score(turn) {
-		if (this._evaluator) {
-			return this._evaluator(this, turn)
-		}
 		const winner = this.winner
 		const nt = this.nextTurn(turn)
 		if (winner === turn) return this._size[0] * this._size[1] * 100 - this._count
diff --git a/lib/rl/reversi.js b/lib/rl/reversi.js
index 700b95ae..3f8b989a 100644
--- a/lib/rl/reversi.js
+++ b/lib/rl/reversi.js
@@ -22,7 +22,7 @@ export default class ReversiRLEnvironment extends RLEnvironmentBase {
 
 		this._size = [8, 8]
 
-		this._board = new ReversiBoard(this._size, this._evaluation)
+		this._board = new ReversiBoard(this._size)
 		this._turn = BLACK
 
 		this._reward = {
@@ -60,16 +60,6 @@ export default class ReversiRLEnvironment extends RLEnvironmentBase {
 		return s
 	}
 
-	set evaluation(func) {
-		if (func) {
-			this._board._evaluator = this._evaluation = (board, turn) => {
-				return func(this._makeState(board, turn, this._turn))
-			}
-		} else {
-			this._board._evaluator = this._evaluation = null
-		}
-	}
-
 	_makeState(board, agentturn, gameturn) {
 		const s = [gameturn]
 		for (let i = 0; i < this._size[0]; i++) {
@@ -82,7 +72,7 @@ export default class ReversiRLEnvironment extends RLEnvironmentBase {
 	}
 
 	_state2board(state, turn) {
-		const board = new ReversiBoard(this._size, this._evaluation)
+		const board = new ReversiBoard(this._size)
 		const opturn = flipPiece(turn)
 		for (let i = 0, p = 1; i < this._size[0]; i++) {
 			for (let j = 0; j < this._size[1]; j++, p++) {
@@ -186,8 +176,7 @@ export default class ReversiRLEnvironment extends RLEnvironmentBase {
 }
 
 class ReversiBoard {
-	constructor(size, evaluator) {
-		this._evaluator = evaluator
+	constructor(size) {
 		this._size = size
 
 		this.reset()
@@ -257,7 +246,7 @@ class ReversiBoard {
 	}
 
 	copy() {
-		const cp = new ReversiBoard(this._size, this._evaluator)
+		const cp = new ReversiBoard(this._size)
 		for (let i = 0; i < this._size[0]; i++) {
 			for (let j = 0; j < this._size[1]; j++) {
 				cp._board[i][j] = this._board[i][j]
@@ -267,9 +256,6 @@ class ReversiBoard {
 	}
 
 	score(turn) {
-		if (this._evaluator) {
-			return this._evaluator(this, turn)
-		}
 		const count = this.count
 		if (turn === BLACK) {
 			return count.black - count.white
diff --git a/tests/lib/rl/draughts.test.js b/tests/lib/rl/draughts.test.js
index 483e6d67..f705ea4c 100644
--- a/tests/lib/rl/draughts.test.js
+++ b/tests/lib/rl/draughts.test.js
@@ -18,27 +18,6 @@ describe('env', () => {
 		expect(env.states).toHaveLength(1 + 8 * 4)
 	})
 
-	describe('evaluation', () => {
-		test('set', () => {
-			const env = new DraughtsRLEnvironment()
-			env.evaluation = state => {
-				expect(state).toHaveLength(1 + 8 * 4)
-				return 1
-			}
-
-			const score = env._board.score()
-			expect(score).toBe(1)
-		})
-
-		test('clear', () => {
-			const env = new DraughtsRLEnvironment()
-			env.evaluation = null
-
-			const score = env._board.score()
-			expect(score).toBe(0)
-		})
-	})
-
 	describe('reset', () => {
 		test('success', () => {
 			const env = new DraughtsRLEnvironment()
diff --git a/tests/lib/rl/gem_puzzle.test.js b/tests/lib/rl/gem_puzzle.test.js
index da51cb39..75a21c4c 100644
--- a/tests/lib/rl/gem_puzzle.test.js
+++ b/tests/lib/rl/gem_puzzle.test.js
@@ -16,29 +16,6 @@ describe('env', () => {
 		}
 	})
 
-	describe('evaluation', () => {
-		test('set', () => {
-			const env = new GemPuzzleRLEnvironment()
-			const n = env._size[0] * env._size[1]
-			env.evaluation = state => {
-				expect(state).toHaveLength(n)
-				return 1
-			}
-
-			const score = env._board.score()
-			expect(score).toBe(1)
-		})
-
-		test('clear', () => {
-			const env = new GemPuzzleRLEnvironment()
-			const orgScore = env._board.score()
-			env.evaluation = null
-
-			const score = env._board.score()
-			expect(score).toBe(orgScore)
-		})
-	})
-
 	test('reset', () => {
 		const env = new GemPuzzleRLEnvironment()
 		const n = env._size[0] * env._size[1]
@@ -228,17 +205,6 @@ describe('board', () => {
 
 			expect(score).toBe(0)
 		})
-
-		test('evaluator', () => {
-			const env = new GemPuzzleRLEnvironment()
-			const board = env._board
-			board._evaluator = () => {
-				return 1
-			}
-			const score = board.score()
-
-			expect(score).toBe(1)
-		})
 	})
 
 	test.todo('at')
diff --git a/tests/lib/rl/gomoku.test.js b/tests/lib/rl/gomoku.test.js
index 9e0c84b5..0e092a2e 100644
--- a/tests/lib/rl/gomoku.test.js
+++ b/tests/lib/rl/gomoku.test.js
@@ -18,27 +18,6 @@ describe('env', () => {
 		expect(env.states).toHaveLength(1 + 8 * 8)
 	})
 
-	describe('evaluation', () => {
-		test('set', () => {
-			const env = new GomokuRLEnvironment()
-			env.evaluation = state => {
-				expect(state).toHaveLength(1 + 8 * 8)
-				return 1
-			}
-
-			const score = env._board.score()
-			expect(score).toBe(1)
-		})
-
-		test('clear', () => {
-			const env = new GomokuRLEnvironment()
-			env.evaluation = null
-
-			const score = env._board.score()
-			expect(score).toBe(0)
-		})
-	})
-
 	describe('reset', () => {
 		test('success', () => {
 			const env = new GomokuRLEnvironment()
@@ -288,6 +267,13 @@ describe('board', () => {
 	})
 
 	describe('score', () => {
+		test('0', () => {
+			const env = new GomokuRLEnvironment()
+			const board = env._board
+
+			expect(board.score(GomokuRLEnvironment.BLACK)).toBe(0)
+		})
+
 		test('win', () => {
 			const env = new GomokuRLEnvironment()
 			const board = env._board
diff --git a/tests/lib/rl/reversi.test.js b/tests/lib/rl/reversi.test.js
index 76e1d5ca..19059d87 100644
--- a/tests/lib/rl/reversi.test.js
+++ b/tests/lib/rl/reversi.test.js
@@ -18,27 +18,6 @@ describe('env', () => {
 		expect(env.states).toHaveLength(1 + 8 * 8)
 	})
 
-	describe('evaluation', () => {
-		test('set', () => {
-			const env = new ReversiRLEnvironment()
-			env.evaluation = state => {
-				expect(state).toHaveLength(1 + 8 * 8)
-				return 1
-			}
-
-			const score = env._board.score()
-			expect(score).toBe(1)
-		})
-
-		test('clear', () => {
-			const env = new ReversiRLEnvironment()
-			env.evaluation = null
-
-			const score = env._board.score()
-			expect(score).toBe(0)
-		})
-	})
-
 	describe('reset', () => {
 		test('success', () => {
 			const env = new ReversiRLEnvironment()