diff --git a/packages/app/src/components/app/play/ui/stamina/index.jsx b/packages/app/src/components/app/play/ui/stamina/index.jsx
index 8211ec3..3441c8f 100644
--- a/packages/app/src/components/app/play/ui/stamina/index.jsx
+++ b/packages/app/src/components/app/play/ui/stamina/index.jsx
@@ -4,8 +4,8 @@ import {PropTypes, React} from '@flecks/react';
 import styles from './index.module.scss';
 
 function Stamina({selfEntity}) {
-  const stamina = usePropertyChange(selfEntity, 'stamina') || 85;
-  const maxStamina = usePropertyChange(selfEntity, 'maxStamina') || 100;
+  const stamina = usePropertyChange(selfEntity, 'stamina');
+  const maxStamina = usePropertyChange(selfEntity, 'maxStamina');
   const filled = stamina / maxStamina;
   return (
     <div
diff --git a/packages/farm/src/traits/tool.js b/packages/farm/src/traits/tool.js
index 0fb850f..babf6a2 100644
--- a/packages/farm/src/traits/tool.js
+++ b/packages/farm/src/traits/tool.js
@@ -85,6 +85,15 @@ export default (flecks) => class Tool extends Trait {
     }
   }
 
+  consumeStamina() {
+    const {wielder} = this.entity;
+    if (wielder.stamina >= this.params.cost) {
+      wielder.stamina -= this.params.cost;
+      return true;
+    }
+    return false;
+  }
+
   createTargetContext(target) {
     const {wielder} = this.entity;
     const {room} = wielder;
@@ -105,6 +114,7 @@ export default (flecks) => class Tool extends Trait {
 
   static defaultParams() {
     return {
+      cost: 3,
       target: {
         type: 'projection',
         distance: 1,
@@ -165,6 +175,9 @@ export default (flecks) => class Tool extends Trait {
     return {
 
       useTool: () => {
+        if (!this.consumeStamina()) {
+          return undefined;
+        }
         this.calculateTargets();
         const promises = this.$$targets.map((target) => {
           const {Script} = flecks.get('$avocado/resource.resources');
diff --git a/packages/inventory/src/packets/trait-update-wielder-stamina.js b/packages/inventory/src/packets/trait-update-wielder-stamina.js
new file mode 100644
index 0000000..32e10ff
--- /dev/null
+++ b/packages/inventory/src/packets/trait-update-wielder-stamina.js
@@ -0,0 +1,12 @@
+import {Packet} from '@flecks/socket';
+
+export default () => class TraitUpdateWielderStamina extends Packet {
+
+  static get data() {
+    return {
+      stamina: 'uint16',
+      maxStamina: 'uint16',
+    };
+  }
+
+};
diff --git a/packages/inventory/src/traits/wielder.js b/packages/inventory/src/traits/wielder.js
index 1f2bf3d..01d6a92 100644
--- a/packages/inventory/src/traits/wielder.js
+++ b/packages/inventory/src/traits/wielder.js
@@ -5,6 +5,12 @@ const decorate = compose(
   StateProperty('activeSlotIndex', {
     track: true,
   }),
+  StateProperty('maxStamina', {
+    track: true,
+  }),
+  StateProperty('stamina', {
+    track: true,
+  }),
 );
 
 export default () => class Wielder extends decorate(Trait) {
@@ -18,9 +24,21 @@ export default () => class Wielder extends decorate(Trait) {
     this.$$itemPromise = undefined;
   }
 
+  acceptPacket(packet) {
+    switch (packet.constructor.type) {
+      case 'TraitUpdateWielderStamina':
+        this.entity.stamina = packet.data.stamina;
+        this.entity.maxStamina = packet.data.maxStamina;
+        break;
+      default:
+    }
+  }
+
   static defaultState() {
     return {
       activeSlotIndex: 0,
+      maxStamina: 100,
+      stamina: 100,
     };
   }
 
@@ -99,6 +117,30 @@ export default () => class Wielder extends decorate(Trait) {
     };
   }
 
+  packetsFor() {
+    const packets = [];
+    const {stamina, maxStamina} = this.stateDifferences();
+    if (stamina || maxStamina) {
+      packets.push([
+        'TraitUpdateWielderStamina',
+        {
+          stamina: this.state.stamina,
+          maxStamina: this.state.maxStamina,
+        },
+      ]);
+    }
+    return packets;
+  }
+
+  get stamina() {
+    return this.state.stamina;
+  }
+
+  set stamina(stamina) {
+    // Clamp stamina between 0 and max.
+    super.stamina = Math.min(Math.max(0, stamina), this.entity.maxStamina);
+  }
+
   tick() {
     if (-1 !== this.$$itemUseRequest && !this.$$itemPromise) {
       const tickingPromise = this.entity.useItemInSlot(this.$$itemUseRequest);