diff --git a/src/common/rpg/components/inventory.ts b/src/common/rpg/components/inventory.ts
index 7649354..e8465af 100644
--- a/src/common/rpg/components/inventory.ts
+++ b/src/common/rpg/components/inventory.ts
@@ -1,6 +1,7 @@
-import type { InventoryOptions, InventorySlotInput, SlotId } from "../types";
+import type { InventorySlotInput, SlotId } from "../types";
 import { action } from "../utils/decorators";
 import { Component } from "../core/world";
+import { Stackable, Usable } from "./item";
 
 interface SlotEntry {
     readonly slotId: SlotId;
@@ -16,9 +17,8 @@ interface SlotUpdateArgs {
 
 export class Inventory extends Component {
     private readonly slots: Map<SlotId, SlotEntry>;
-    private readonly maxAmountPerItem: Record<string, number>;
 
-    constructor(slotDefs: Array<InventorySlotInput>, options?: InventoryOptions) {
+    constructor(slotDefs: Array<InventorySlotInput>) {
         super();
         this.slots = new Map(
             slotDefs.map(def => {
@@ -27,17 +27,15 @@ export class Inventory extends Component {
                 return [slotId, { slotId, limit, state: null }];
             })
         );
-        this.maxAmountPerItem = options?.maxAmountPerItem ?? {};
     }
 
-    // Max amount of itemId allowed in a single slot (min of slot.limit and maxAmountPerItem cap)
     private slotCapFor(slot: SlotEntry, itemId: string): number {
         const limitCap = slot.limit ?? Infinity;
-        const itemCap = this.maxAmountPerItem[itemId] ?? Infinity;
-        return Math.min(limitCap, itemCap);
+        const stackable = this.entity.world.getEntity(itemId)?.get(Stackable);
+        const stackCap = stackable ? stackable.maxStack : 1;
+        return Math.min(limitCap, stackCap);
     }
 
-    // Remaining space in slot for itemId
     private slotRoomFor(slot: SlotEntry, itemId: string): number {
         if (slot.state !== null && slot.state.itemId !== itemId) return 0;
         return this.slotCapFor(slot, itemId) - (slot.state?.amount ?? 0);
@@ -48,6 +46,11 @@ export class Inventory extends Component {
         if (amount < 0) return false;
         if (amount === 0) return true;
 
+        if (!this.entity.world.getEntity(itemId)) {
+            console.warn(`[Inventory] add: item entity '${itemId}' not found`);
+            return false;
+        }
+
         if (slotId !== undefined) {
             const slot = this.slots.get(slotId);
             if (!slot) return false;
@@ -134,6 +137,35 @@ export class Inventory extends Component {
         return false;
     }
 
+    @action
+    async use(itemId?: string): Promise<boolean> {
+        if (!itemId) return false;
+
+        if (this.getAmount(itemId) === 0) {
+            console.warn(`[Inventory] use: item '${itemId}' not in inventory`);
+            return false;
+        }
+
+        const itemEntity = this.entity.world.getEntity(itemId);
+        if (!itemEntity) {
+            console.warn(`[Inventory] use: item entity '${itemId}' not found`);
+            return false;
+        }
+
+        const usable = itemEntity.get(Usable);
+        if (!usable) {
+            console.warn(`[Inventory] use: item '${itemId}' has no Usable component`);
+            return false;
+        }
+
+        if (usable.consumeOnUse) {
+            this.remove({ itemId, amount: 1 });
+        }
+
+        await usable.use({ self: this.entity, world: this.entity.world });
+        return true;
+    }
+
     getAmount(itemId: string, slotId?: SlotId): number {
         if (slotId !== undefined) {
             const slot = this.slots.get(slotId);
diff --git a/src/common/rpg/components/item.ts b/src/common/rpg/components/item.ts
new file mode 100644
index 0000000..e562e6e
--- /dev/null
+++ b/src/common/rpg/components/item.ts
@@ -0,0 +1,36 @@
+import { Component, type EvalContext } from "../core/world";
+import type { RPGAction } from "../types";
+import { action, variable } from "../utils/decorators";
+import { executeAction } from "../utils/variables";
+
+export class Item extends Component {
+    constructor(
+        readonly name: string,
+        readonly description: string = '',
+    ) {
+        super();
+    }
+}
+
+export class Stackable extends Component {
+    @variable readonly maxStack: number;
+    constructor(maxStack: number) {
+        super();
+        this.maxStack = maxStack;
+    }
+}
+
+export class Usable extends Component {
+    @variable readonly consumeOnUse: boolean;
+    constructor(private readonly actions: RPGAction[], consumeOnUse = true) {
+        super();
+        this.consumeOnUse = consumeOnUse;
+    }
+
+    @action
+    async use(ctx: EvalContext): Promise<void> {
+        for (const action of this.actions) {
+            await executeAction(action, ctx);
+        }
+    }
+}
diff --git a/src/common/rpg/core/world.ts b/src/common/rpg/core/world.ts
index 374ba92..17d560e 100644
--- a/src/common/rpg/core/world.ts
+++ b/src/common/rpg/core/world.ts
@@ -70,7 +70,7 @@ export class Entity {
 
     constructor(
         readonly id: string,
-        private readonly world: World,
+        readonly world: World,
     ) { }
 
     add<T extends Component>(key: string, component: T): T {
diff --git a/src/common/rpg/types.ts b/src/common/rpg/types.ts
index ca150f1..68540c8 100644
--- a/src/common/rpg/types.ts
+++ b/src/common/rpg/types.ts
@@ -12,6 +12,7 @@ export type RPGVariables = Record<string, string | number | boolean | undefined>
 export type RPGActions = Record<string, (arg?: any) => unknown>;
 export type RPGAction = Static<typeof RPGActionScheme>;
 
+
 // ── Dialog ────────────────────────────────────────────────────────────────────
 
 const DialogChoiceScheme = Type.Object({
@@ -85,6 +86,4 @@ export interface InventorySlotDefinition {
 
 export type InventorySlotInput = SlotId | InventorySlotDefinition;
 
-export interface InventoryOptions {
-    maxAmountPerItem?: Record<string, number>;
-}
+