diff --git a/src/data/arena-tag.ts b/src/data/arena-tag.ts
index fdc32b75c196..96a40cae536d 100644
--- a/src/data/arena-tag.ts
+++ b/src/data/arena-tag.ts
@@ -824,6 +824,31 @@ export class TrickRoomTag extends ArenaTag {
   }
 }
 
+/**
+ * Arena Tag class for {@link https://bulbapedia.bulbagarden.net/wiki/Wonder_Room_(move) Wonder Room}.
+ * Swaps the Defense and Special Defense stats for all Pokémon on the field as long as this arena tag is up,
+ * also reversing the turn order for all Pokémon on the field as well.
+ */
+export class WonderRoomTag extends ArenaTag {
+  constructor(turnCount: integer) {
+    super(ArenaTagType.WONDER_ROOM, turnCount, Moves.WONDER_ROOM);
+  }
+
+  apply(arena: Arena, args: any[]): boolean {
+    const isWonderRoom = args[0] as Utils.BooleanHolder;
+    isWonderRoom.value = !isWonderRoom.value;
+    return true;
+  }
+
+  onAdd(arena: Arena): void {
+    arena.scene.queueMessage(i18next.t("arenaTag:wonderRoomOnAdd"));
+  }
+
+  onRemove(arena: Arena): void {
+    arena.scene.queueMessage(i18next.t("arenaTag:wonderRoomOnRemove"));
+  }
+}
+
 /**
  * Arena Tag class for {@link https://bulbapedia.bulbagarden.net/wiki/Gravity_(move) Gravity}.
  * Grounds all Pokémon on the field, including Flying-types and those with
@@ -965,6 +990,8 @@ export function getArenaTag(tagType: ArenaTagType, turnCount: integer, sourceMov
     return new TailwindTag(turnCount, sourceId, side);
   case ArenaTagType.HAPPY_HOUR:
     return new HappyHourTag(turnCount, sourceId, side);
+  case ArenaTagType.WONDER_ROOM:
+    return new WonderRoomTag(turnCount);
   case ArenaTagType.SAFEGUARD:
     return new SafeguardTag(turnCount, sourceId, side);
   default:
diff --git a/src/data/move.ts b/src/data/move.ts
index 8866e86f708a..0ba5b93ff43d 100644
--- a/src/data/move.ts
+++ b/src/data/move.ts
@@ -8100,9 +8100,10 @@ export function initMoves() {
     new StatusMove(Moves.POWER_SPLIT, Type.PSYCHIC, -1, 10, -1, 0, 5)
       .attr(AverageStatsAttr, [ Stat.ATK, Stat.SPATK ], "moveTriggers:sharedPower"),
     new StatusMove(Moves.WONDER_ROOM, Type.PSYCHIC, -1, 10, -1, 0, 5)
+      .attr(AddArenaTagAttr, ArenaTagType.WONDER_ROOM, 5)
       .ignoresProtect()
       .target(MoveTarget.BOTH_SIDES)
-      .unimplemented(),
+      .partial(),
     new AttackMove(Moves.PSYSHOCK, Type.PSYCHIC, MoveCategory.SPECIAL, 80, 100, 10, -1, 0, 5)
       .attr(DefDefAttr),
     new AttackMove(Moves.VENOSHOCK, Type.POISON, MoveCategory.SPECIAL, 65, 100, 10, -1, 0, 5)
diff --git a/src/enums/arena-tag-type.ts b/src/enums/arena-tag-type.ts
index 1c79750c91ab..921351742959 100644
--- a/src/enums/arena-tag-type.ts
+++ b/src/enums/arena-tag-type.ts
@@ -23,5 +23,6 @@ export enum ArenaTagType {
   TAILWIND = "TAILWIND",
   HAPPY_HOUR = "HAPPY_HOUR",
   SAFEGUARD = "SAFEGUARD",
-  NO_CRIT = "NO_CRIT"
+  NO_CRIT = "NO_CRIT",
+  WONDER_ROOM = "WONDER_ROOM"
 }
diff --git a/src/field/pokemon.ts b/src/field/pokemon.ts
index 14f938094149..d6788c343a30 100644
--- a/src/field/pokemon.ts
+++ b/src/field/pokemon.ts
@@ -19,7 +19,7 @@ import { pokemonEvolutions, pokemonPrevolutions, SpeciesFormEvolution, SpeciesEv
 import { reverseCompatibleTms, tmSpecies, tmPoolTiers } from "../data/tms";
 import { BattlerTag, BattlerTagLapseType, EncoreTag, GroundedTag, HighestStatBoostTag, SubstituteTag, TypeImmuneTag, getBattlerTag, SemiInvulnerableTag, TypeBoostTag, MoveRestrictionBattlerTag, ExposedTag, DragonCheerTag, CritBoostTag, TrappedTag, TarShotTag, AutotomizedTag } from "../data/battler-tags";
 import { WeatherType } from "../data/weather";
-import { ArenaTagSide, NoCritTag, WeakenMoveScreenTag } from "../data/arena-tag";
+import { ArenaTagSide, NoCritTag, WeakenMoveScreenTag, WonderRoomTag } from "../data/arena-tag";
 import { Ability, AbAttr, StatMultiplierAbAttr, BlockCritAbAttr, BonusCritAbAttr, BypassBurnDamageReductionAbAttr, FieldPriorityMoveImmunityAbAttr, IgnoreOpponentStatStagesAbAttr, MoveImmunityAbAttr, PreDefendFullHpEndureAbAttr, ReceivedMoveDamageMultiplierAbAttr, ReduceStatusEffectDurationAbAttr, StabBoostAbAttr, StatusEffectImmunityAbAttr, TypeImmunityAbAttr, WeightMultiplierAbAttr, allAbilities, applyAbAttrs, applyStatMultiplierAbAttrs, applyPreApplyBattlerTagAbAttrs, applyPreAttackAbAttrs, applyPreDefendAbAttrs, applyPreSetStatusAbAttrs, UnsuppressableAbilityAbAttr, SuppressFieldAbilitiesAbAttr, NoFusionAbilityAbAttr, MultCritAbAttr, IgnoreTypeImmunityAbAttr, DamageBoostAbAttr, IgnoreTypeStatusEffectImmunityAbAttr, ConditionalCritAbAttr, applyFieldStatMultiplierAbAttrs, FieldMultiplyStatAbAttr, AddSecondStrikeAbAttr, UserFieldStatusEffectImmunityAbAttr, UserFieldBattlerTagImmunityAbAttr, BattlerTagImmunityAbAttr, MoveTypeChangeAbAttr, FullHpResistTypeAbAttr, applyCheckTrappedAbAttrs, CheckTrappedAbAttr, PostSetStatusAbAttr, applyPostSetStatusAbAttrs } from "../data/ability";
 import PokemonData from "../system/pokemon-data";
 import { BattlerIndex } from "../battle";
@@ -769,7 +769,11 @@ export default abstract class Pokemon extends Phaser.GameObjects.Container {
     if (!bypassSummonData && this.summonData?.stats) {
       return this.summonData.stats;
     }
-    return this.stats;
+    const isWonderRoom = new Utils.BooleanHolder(false);
+    this.scene.arena.applyTags(WonderRoomTag, isWonderRoom);
+    return isWonderRoom.value
+      ? [this.stats[Stat.HP], this.stats[Stat.ATK], this.stats[Stat.SPDEF], this.stats[Stat.SPATK], this.stats[Stat.DEF], this.stats[Stat.SPD]]
+      : this.stats;
   }
 
   /**