diff --git a/src/core/move_generator.gd b/src/core/move_generator.gd
index 67373d7..eea2fcb 100644
--- a/src/core/move_generator.gd
+++ b/src/core/move_generator.gd
@@ -10,10 +10,10 @@ const BEAM_WIDTH := 50
 
 static func generate(hand: Array[Card], current_rank: int, config: RuleConfig) -> Array[HandEvaluator.EvaluatedPlay]:
     var results: Array[HandEvaluator.EvaluatedPlay] = []
-    var pass := HandEvaluator.EvaluatedPlay.new()
-    pass.type = -1
-    pass.primary_rank = 0
-    results.append(pass)
+    var pass_play := HandEvaluator.EvaluatedPlay.new()
+    pass_play.type = -1
+    pass_play.primary_rank = 0
+    results.append(pass_play)
     if hand.is_empty():
         return results
     var sorted := hand.duplicate(false)
diff --git a/src/game/game_controller.gd b/src/game/game_controller.gd
index 604fef7..1faf97e 100644
--- a/src/game/game_controller.gd
+++ b/src/game/game_controller.gd
@@ -45,10 +45,10 @@ func handle_human_pass() -> Dictionary:
     var old_last := game_state.round.last_non_pass_player()
     if old_last >= 0 and old_last == game_state.round.active_player_idx:
         return {"ok": false, "error_code": 3, "data": null}
-    var pass := HandEvaluator.EvaluatedPlay.new()
-    pass.type = -1
-    pass.primary_rank = 0
-    _apply_play(game_state.round.active_player_idx, pass)
+    var pass_play := HandEvaluator.EvaluatedPlay.new()
+    pass_play.type = -1
+    pass_play.primary_rank = 0
+    _apply_play(game_state.round.active_player_idx, pass_play)
     _advance_turn()
     return {"ok": true, "error_code": 0, "data": null}
 
diff --git a/tests/hello.gd b/tests/hello.gd
new file mode 100644
index 0000000..8162af3
--- /dev/null
+++ b/tests/hello.gd
@@ -0,0 +1,4 @@
+extends Node
+func _ready():
+    print("hello")
+    get_tree().quit(0)
diff --git a/tests/quick_test.gd b/tests/quick_test.gd
new file mode 100644
index 0000000..a3b26f8
--- /dev/null
+++ b/tests/quick_test.gd
@@ -0,0 +1,47 @@
+extends Node
+
+func _ready():
+    print("=== Guandan Card Game - Core Logic Test ===\n")
+    
+    var config := RuleConfig.standard()
+    var deck := Deck.create(42)
+    print("Deck: %d cards" % deck.remaining())
+    assert(deck.remaining() == 108, "deck size")
+    
+    deck = Deck.create(42)
+    deck.deal(108)
+    assert(deck.remaining() == 0, "deal all")
+    
+    var d1 := Deck.create(42)
+    var d2 := Deck.create(42)
+    var h1 := d1.deal(27)
+    var h2 := d2.deal(27)
+    var deterministic := true
+    for i in range(27):
+        if h1[i].card_id != h2[i].card_id: deterministic = false
+    assert(deterministic, "shuffle deterministic")
+    
+    var gs := GameState.create(config, 42)
+    assert(gs.current_rank == 2, "start level 2")
+    
+    var t := Actions.Team.create_team(0, 0, 2)
+    assert(t.teammate_of(0) == 2, "teammate")
+    
+    var l1 := L1BasicAI.new()
+    var hand: Array = [h1[0]]
+    var decision := l1.decide(hand, [], 5, config)
+    assert(decision.type != -2, "L1 AI returns valid result")
+    
+    var l2 := L2RuleAI.new()
+    var decision2 := l2.decide(hand, [], 5, config)
+    assert(decision2.type != -2, "L2 AI returns valid result")
+    
+    print("\n=== ALL TESTS PASSED ===")
+    get_tree().quit(0)
+
+func assert(condition: bool, name: String):
+    if condition:
+        print("  PASS: %s" % name)
+    else:
+        printerr("  FAIL: %s" % name)
+        get_tree().quit(1)