diff --git a/src/data/ability.ts b/src/data/ability.ts
index 019c78a91f0..0286d087093 100644
--- a/src/data/ability.ts
+++ b/src/data/ability.ts
@@ -6,7 +6,7 @@ import { BattleStat, getBattleStatName } from "./battle-stat";
 import { MovePhase, PokemonHealPhase, ShowAbilityPhase, StatChangePhase } from "../phases";
 import { getPokemonMessage, getPokemonNameWithAffix } from "../messages";
 import { Weather, WeatherType } from "./weather";
-import { BattlerTag } from "./battler-tags";
+import { BattlerTag, GroundedTag } from "./battler-tags";
 import { StatusEffect, getNonVolatileStatusEffects, getStatusEffectDescriptor, getStatusEffectHealText } from "./status-effect";
 import { Gender } from "./gender";
 import Move, { AttackMove, MoveCategory, MoveFlags, MoveTarget, FlinchAttr, OneHitKOAttr, HitHealAttr, allMoves, StatusMove, SelfStatusMove, VariablePowerAttr, applyMoveAttrs, IncrementMovePriorityAttr, VariableMoveTypeAttr, RandomMovesetMoveAttr, RandomMoveAttr, NaturePowerAttr, CopyMoveAttr  } from "./move";
@@ -4110,7 +4110,7 @@ export function initAbilities() {
       .attr(UnswappableAbilityAbAttr)
       .ignorable(),
     new Ability(Abilities.LEVITATE, 3)
-      .attr(TypeImmunityAbAttr, Type.GROUND, (pokemon: Pokemon) => !pokemon.getTag(BattlerTagType.IGNORE_FLYING) && !pokemon.scene.arena.getTag(ArenaTagType.GRAVITY) && !pokemon.getTag(BattlerTagType.GROUNDED))
+      .attr(TypeImmunityAbAttr, Type.GROUND, (pokemon: Pokemon) => !pokemon.getTag(GroundedTag) && !pokemon.scene.arena.getTag(ArenaTagType.GRAVITY))
       .ignorable(),
     new Ability(Abilities.EFFECT_SPORE, 3)
       .attr(EffectSporeAbAttr),
diff --git a/src/data/battler-tags.ts b/src/data/battler-tags.ts
index 4e2a4e06d3c..0880d6948f8 100644
--- a/src/data/battler-tags.ts
+++ b/src/data/battler-tags.ts
@@ -1467,6 +1467,17 @@ export class CursedTag extends BattlerTag {
   }
 }
 
+/**
+ * Battler tag for effects that ground the source, allowing Ground-type moves to hit them. Encompasses two tag types:
+ * @item IGNORE_FLYING: Persistent grounding effects (i.e. from Smack Down and Thousand Waves)
+ * @item ROOSTED: One-turn grounding effects (i.e. from Roost)
+ */
+export class GroundedTag extends BattlerTag {
+  constructor(tagType: BattlerTagType, lapseType: BattlerTagLapseType, sourceMove: Moves) {
+    super(tagType, lapseType, 1, sourceMove);
+  }
+}
+
 /**
  * Provides the Ice Face ability's effects.
  */
@@ -1618,9 +1629,9 @@ export function getBattlerTag(tagType: BattlerTagType, turnCount: integer, sourc
   case BattlerTagType.BYPASS_SLEEP:
     return new BattlerTag(BattlerTagType.BYPASS_SLEEP, BattlerTagLapseType.TURN_END, turnCount, sourceMove);
   case BattlerTagType.IGNORE_FLYING:
-    return new BattlerTag(tagType, BattlerTagLapseType.TURN_END, turnCount, sourceMove);
-  case BattlerTagType.GROUNDED:
-    return new BattlerTag(tagType, BattlerTagLapseType.TURN_END, turnCount - 1, sourceMove);
+    return new GroundedTag(tagType, BattlerTagLapseType.CUSTOM, sourceMove);
+  case BattlerTagType.ROOSTED:
+    return new GroundedTag(tagType, BattlerTagLapseType.TURN_END, sourceMove);
   case BattlerTagType.SALT_CURED:
     return new SaltCuredTag(sourceId);
   case BattlerTagType.CURSED:
diff --git a/src/data/move.ts b/src/data/move.ts
index 3b7ed896ea0..151021f7f9d 100644
--- a/src/data/move.ts
+++ b/src/data/move.ts
@@ -6606,7 +6606,7 @@ export function initMoves() {
       .attr(StatChangeAttr, BattleStat.SPATK, -2, true),
     new SelfStatusMove(Moves.ROOST, Type.FLYING, -1, 5, -1, 0, 4)
       .attr(HealAttr, 0.5)
-      .attr(AddBattlerTagAttr, BattlerTagType.GROUNDED, true, false, 1)
+      .attr(AddBattlerTagAttr, BattlerTagType.ROOSTED, true, false)
       .triageMove(),
     new StatusMove(Moves.GRAVITY, Type.PSYCHIC, -1, 5, -1, 0, 4)
       .attr(AddArenaTagAttr, ArenaTagType.GRAVITY, 5)
@@ -6947,7 +6947,7 @@ export function initMoves() {
       .target(MoveTarget.BOTH_SIDES)
       .unimplemented(),
     new AttackMove(Moves.SMACK_DOWN, Type.ROCK, MoveCategory.PHYSICAL, 50, 100, 15, 100, 0, 5)
-      .attr(AddBattlerTagAttr, BattlerTagType.IGNORE_FLYING, false, false, 5)
+      .attr(AddBattlerTagAttr, BattlerTagType.IGNORE_FLYING, false, false)
       .attr(AddBattlerTagAttr, BattlerTagType.INTERRUPTED)
       .attr(RemoveBattlerTagAttr, [BattlerTagType.FLYING, BattlerTagType.MAGNET_RISEN])
       .attr(HitsTagAttr, BattlerTagType.FLYING, false)
@@ -7331,7 +7331,7 @@ export function initMoves() {
       .triageMove(),
     new AttackMove(Moves.THOUSAND_ARROWS, Type.GROUND, MoveCategory.PHYSICAL, 90, 100, 10, -1, 0, 6)
       .attr(NeutralDamageAgainstFlyingTypeMultiplierAttr)
-      .attr(AddBattlerTagAttr, BattlerTagType.IGNORE_FLYING, false, false, 20) // TODO: remove this turn count
+      .attr(AddBattlerTagAttr, BattlerTagType.IGNORE_FLYING, false, false)
       .attr(HitsTagAttr, BattlerTagType.FLYING, false)
       .attr(AddBattlerTagAttr, BattlerTagType.INTERRUPTED)
       .attr(RemoveBattlerTagAttr, [BattlerTagType.FLYING, BattlerTagType.MAGNET_RISEN])
diff --git a/src/enums/battler-tag-type.ts b/src/enums/battler-tag-type.ts
index 4d212a2da12..5cdabfe78c2 100644
--- a/src/enums/battler-tag-type.ts
+++ b/src/enums/battler-tag-type.ts
@@ -54,7 +54,7 @@ export enum BattlerTagType {
   SALT_CURED = "SALT_CURED",
   CURSED = "CURSED",
   CHARGED = "CHARGED",
-  GROUNDED = "GROUNDED",
+  ROOSTED = "ROOSTED",
   MAGNET_RISEN = "MAGNET_RISEN",
   MINIMIZED = "MINIMIZED",
   DESTINY_BOND = "DESTINY_BOND",
diff --git a/src/field/pokemon.ts b/src/field/pokemon.ts
index 45ea72ef500..05ed21e732c 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 { DamagePhase, FaintPhase, LearnMovePhase, ObtainStatusEffectPhase, StatChangePhase, SwitchSummonPhase, ToggleDoublePositionPhase  } from "../phases";
 import { BattleStat } from "../data/battle-stat";
-import { BattlerTag, BattlerTagLapseType, EncoreTag, HelpingHandTag, HighestStatBoostTag, TypeBoostTag, TypeImmuneTag, getBattlerTag } from "../data/battler-tags";
+import { BattlerTag, BattlerTagLapseType, EncoreTag, GroundedTag, HelpingHandTag, HighestStatBoostTag, TypeBoostTag, TypeImmuneTag, getBattlerTag } from "../data/battler-tags";
 import { WeatherType } from "../data/weather";
 import { TempBattleStat } from "../data/temp-battle-stat";
 import { ArenaTagSide, WeakenMoveScreenTag, WeakenMoveTypeTag } from "../data/arena-tag";
@@ -884,7 +884,7 @@ export default abstract class Pokemon extends Phaser.GameObjects.Container {
       }
     }
 
-    if (forDefend && (this.getTag(BattlerTagType.IGNORE_FLYING) || this.scene.arena.getTag(ArenaTagType.GRAVITY) || this.getTag(BattlerTagType.GROUNDED))) {
+    if (forDefend && (this.getTag(GroundedTag) || this.scene.arena.getTag(ArenaTagType.GRAVITY))) {
       const flyingIndex = types.indexOf(Type.FLYING);
       if (flyingIndex > -1) {
         types.splice(flyingIndex, 1);
@@ -1097,7 +1097,7 @@ export default abstract class Pokemon extends Phaser.GameObjects.Container {
   }
 
   isGrounded(): boolean {
-    return !this.isOfType(Type.FLYING, true, true) && !this.hasAbility(Abilities.LEVITATE) && !this.getTag(BattlerTagType.MAGNET_RISEN);
+    return !!this.getTag(GroundedTag) || (!this.isOfType(Type.FLYING, true, true) && !this.hasAbility(Abilities.LEVITATE) && !this.getTag(BattlerTagType.MAGNET_RISEN));
   }
 
   /**
diff --git a/src/test/moves/roost.test.ts b/src/test/moves/roost.test.ts
new file mode 100644
index 00000000000..db9363313a1
--- /dev/null
+++ b/src/test/moves/roost.test.ts
@@ -0,0 +1,64 @@
+import {afterEach, beforeAll, beforeEach, describe, expect, test, vi} from "vitest";
+import Phaser from "phaser";
+import GameManager from "#app/test/utils/gameManager";
+import * as overrides from "#app/overrides";
+import { Species } from "#app/enums/species.js";
+import { Moves } from "#app/enums/moves.js";
+import { getMovePosition } from "../utils/gameManagerUtils";
+import { MoveEffectPhase, TurnEndPhase } from "#app/phases.js";
+import { BattlerTagType } from "#app/enums/battler-tag-type.js";
+import { Abilities } from "#app/enums/abilities.js";
+
+const TIMEOUT = 20 * 1000;
+
+describe("Moves - Roost", () => {
+  let phaserGame: Phaser.Game;
+  let game: GameManager;
+
+  beforeAll(() => {
+    phaserGame = new Phaser.Game({
+      type: Phaser.HEADLESS,
+    });
+  });
+
+  afterEach(() => {
+    game.phaseInterceptor.restoreOg();
+  });
+
+  beforeEach(() => {
+    game = new GameManager(phaserGame);
+    vi.spyOn(overrides, "SINGLE_BATTLE_OVERRIDE", "get").mockReturnValue(true);
+    vi.spyOn(overrides, "OPP_SPECIES_OVERRIDE", "get").mockReturnValue(Species.STARAPTOR);
+    vi.spyOn(overrides, "OPP_ABILITY_OVERRIDE", "get").mockReturnValue(Abilities.INSOMNIA);
+    vi.spyOn(overrides, "STARTING_LEVEL_OVERRIDE", "get").mockReturnValue(100);
+    vi.spyOn(overrides, "OPP_LEVEL_OVERRIDE", "get").mockReturnValue(100);
+    vi.spyOn(overrides, "MOVESET_OVERRIDE", "get").mockReturnValue([ Moves.STOMPING_TANTRUM ]);
+    vi.spyOn(overrides, "OPP_MOVESET_OVERRIDE", "get").mockReturnValue([Moves.ROOST,Moves.ROOST,Moves.ROOST,Moves.ROOST]);
+  });
+
+  test(
+    "move should ground the user until the end of turn",
+    async () => {
+      await game.startBattle([Species.MAGIKARP]);
+
+      const leadPokemon = game.scene.getPlayerPokemon();
+      expect(leadPokemon).toBeDefined();
+
+      const enemyPokemon = game.scene.getEnemyPokemon();
+      expect(enemyPokemon).toBeDefined();
+
+      const enemyStartingHp = enemyPokemon.hp;
+
+      game.doAttack(getMovePosition(game.scene, 0, Moves.STOMPING_TANTRUM));
+
+      await game.phaseInterceptor.to(MoveEffectPhase);
+
+      expect(enemyPokemon.getTag(BattlerTagType.ROOSTED)).toBeDefined();
+
+      await game.phaseInterceptor.to(TurnEndPhase);
+
+      expect(enemyPokemon.hp).toBeLessThan(enemyStartingHp);
+      expect(enemyPokemon.getTag(BattlerTagType.ROOSTED)).toBeUndefined();
+    }, TIMEOUT
+  );
+});
diff --git a/src/test/moves/thousand_arrows.test.ts b/src/test/moves/thousand_arrows.test.ts
index 08b4edfd313..c641643593e 100644
--- a/src/test/moves/thousand_arrows.test.ts
+++ b/src/test/moves/thousand_arrows.test.ts
@@ -57,7 +57,7 @@ describe("Moves - Thousand Arrows", () => {
       // Enemy should not be grounded before move effect is applied
       expect(enemyPokemon.getTag(BattlerTagType.IGNORE_FLYING)).toBeUndefined();
 
-      await game.phaseInterceptor.to(TurnEndPhase, false);
+      await game.phaseInterceptor.to(TurnEndPhase);
 
       expect(enemyPokemon.getTag(BattlerTagType.IGNORE_FLYING)).toBeDefined();
       expect(enemyPokemon.hp).toBeLessThan(enemyStartingHp);