From 3d5a46b1ec229031b71bcfbb829e6cfb00714d4f Mon Sep 17 00:00:00 2001
From: Fabi <192151969+fabske0@users.noreply.github.com>
Date: Mon, 27 Oct 2025 19:37:33 +0100
Subject: [PATCH] [BUG] Fix quick claw being blocked by Psychic terrain (#6684)

* Fix quick claw being blocked

* Add tests

* Apply suggestions from code review

Co-authored-by: Bertie690 <136088738+Bertie690@users.noreply.github.com>

* fix test + run biome

* Update comments in `terrain.ts`

* Apply test suggestions

* added newlines

---------

Co-authored-by: Bertie690 <136088738+Bertie690@users.noreply.github.com>
Co-authored-by: NightKev <34855794+DayKev@users.noreply.github.com>
---
 src/data/terrain.ts                |  6 ++--
 test/arena/psychic-terrain.test.ts | 44 ++++++++++++++++++++++++++++++
 2 files changed, 46 insertions(+), 4 deletions(-)

diff --git a/src/data/terrain.ts b/src/data/terrain.ts
index 315ed919e03..bd90f3985b4 100644
--- a/src/data/terrain.ts
+++ b/src/data/terrain.ts
@@ -64,12 +64,10 @@ export class Terrain {
     switch (this.terrainType) {
       case TerrainType.PSYCHIC:
         // Cf https://bulbapedia.bulbagarden.net/wiki/Psychic_Terrain_(move)#Generation_VII
-        // Psychic terrain will only cancel a move if it:
         return (
-          // ... is neither spread nor field-targeted,
           !isFieldTargeted(move)
-          && !isSpreadMove(move) // .. has positive final priority,
-          && move.getPriority(user) > 0 // ...and is targeting at least 1 grounded opponent
+          && !isSpreadMove(move)
+          && move.getPriority(user) > 0.2 // fractional priority is used by quick claw etc and is not blocked by terrain
           && user.getOpponents(true).some(o => targets.includes(o.getBattlerIndex()) && o.isGrounded())
         );
     }
diff --git a/test/arena/psychic-terrain.test.ts b/test/arena/psychic-terrain.test.ts
index 6d42ed0d3ac..6112db41cd8 100644
--- a/test/arena/psychic-terrain.test.ts
+++ b/test/arena/psychic-terrain.test.ts
@@ -1,3 +1,5 @@
+import { allMoves } from "#data/data-lists";
+import { TerrainType } from "#data/terrain";
 import { AbilityId } from "#enums/ability-id";
 import { MoveId } from "#enums/move-id";
 import { SpeciesId } from "#enums/species-id";
@@ -56,4 +58,46 @@ describe("Arena - Psychic Terrain", () => {
 
     expect(game.scene.arena.weather?.weatherType).toBe(WeatherType.RAIN);
   });
+
+  it("should not block non-priority moves boosted by Quick Claw", async () => {
+    game.override.startingHeldItems([{ name: "QUICK_CLAW", count: 10 }]);
+    await game.classicMode.startBattle([SpeciesId.FEEBAS]);
+
+    game.move.use(MoveId.PSYCHIC_TERRAIN);
+    await game.toNextTurn();
+
+    expect(game).toHaveTerrain(TerrainType.PSYCHIC);
+
+    game.move.use(MoveId.POUND);
+    await game.phaseInterceptor.to("MovePhase", false);
+
+    const feebas = game.field.getPlayerPokemon();
+    expect(allMoves[MoveId.POUND].getPriority(feebas)).toBe(0.2);
+
+    await game.toEndOfTurn();
+
+    const shuckle = game.field.getEnemyPokemon();
+    expect(shuckle).not.toHaveFullHp();
+  });
+
+  it("should block priority moves boosted by Quick Claw", async () => {
+    game.override.startingHeldItems([{ name: "QUICK_CLAW", count: 10 }]);
+    await game.classicMode.startBattle([SpeciesId.FEEBAS]);
+
+    game.move.use(MoveId.PSYCHIC_TERRAIN);
+    await game.toNextTurn();
+
+    expect(game).toHaveTerrain(TerrainType.PSYCHIC);
+
+    game.move.use(MoveId.QUICK_ATTACK);
+    await game.phaseInterceptor.to("MovePhase", false);
+
+    const feebas = game.field.getPlayerPokemon();
+    expect(allMoves[MoveId.QUICK_ATTACK].getPriority(feebas)).toBe(1.2);
+
+    await game.toEndOfTurn();
+
+    const shuckle = game.field.getEnemyPokemon();
+    expect(shuckle).toHaveFullHp();
+  });
 });