diff --git a/src/client/InteractionClient.js b/src/client/InteractionClient.js
index d7d13065..ffb1faec 100644
--- a/src/client/InteractionClient.js
+++ b/src/client/InteractionClient.js
@@ -1,6 +1,7 @@
 'use strict';
 
 const BaseClient = require('./BaseClient');
+const APIMessage = require('../structures/APIMessage');
 const Interaction = require('../structures/Interaction');
 const { ApplicationCommandOptionType, InteractionType, InteractionResponseType } = require('../util/Constants');
 
@@ -37,6 +38,7 @@ class InteractionClient extends BaseClient {
     super(options);
     this.client = client || this;
     this.handler = handler;
+    this.token = options.token;
     this.publicKey = options.publicKey ? Buffer.from(options.publicKey, 'hex') : undefined;
   }
 
@@ -87,44 +89,72 @@ class InteractionClient extends BaseClient {
           type: InteractionResponseType.PONG,
         };
       case InteractionType.APPLICATION_COMMAND: {
-        try {
-          const interaction = new Interaction(this.client, data);
-          const result = await this.handler(interaction);
-          if (result === null) {
-            return {
-              type: InteractionResponseType.ACKNOWLEDGE,
-            };
+        const interaction = new Interaction(this.client, data);
+
+        let done = false;
+        const r0 = new Promise(resolve => {
+          this.client.setTimeout(() => {
+            done = true;
+            resolve({
+              type: InteractionResponseType.ACKNOWLEDGE_WITH_SOURCE,
+            });
+          }, 500);
+        });
+        const r1 = this.handler(interaction).then(async r => {
+          if (done) {
+            interaction.reply(r).catch(e => {
+              this.client.emit('error', e);
+            });
+            return undefined;
           }
-          // handle result as message resolvable here, probably DRY this branch with code in
-          // `Interaction#reply`, except `Interaction#reply` obviously does a POST and this just
-          // returns the data.
-          throw new Error('fucc');
-        } catch (e) {
-          this.client.emit('error', e);
+
+          let apiMessage;
+
+          if (r instanceof APIMessage) {
+            apiMessage = r.resolveData();
+          } else {
+            apiMessage = APIMessage.create(interaction, r).resolveData();
+            if (Array.isArray(apiMessage.data.content)) {
+              throw new Error();
+            }
+          }
+
+          const resolved = await apiMessage.resolveFiles();
           return {
-            type: InteractionResponseType.ACKNOWLEDGE,
+            type: InteractionResponseType.CHANNEL_MESSAGE_WITH_SOURCE,
+            data: resolved.data,
           };
-        }
+        });
+
+        const result = await Promise.race([r0, r1]);
+
+        return result;
       }
       default:
         throw new RangeError('Invalid interaction data');
     }
   }
 
-  async handleFromHTTP(body, signature) {
+  async handleFromHTTP(body, signature, timestamp) {
     if (sodium === undefined) {
       sodium = require('../util/Sodium');
     }
-    if (!sodium.methods.verify(Buffer.from(signature, 'hex'), Buffer.from(body), this.publicKey)) {
-      throw new Error('Invalid signature');
+    if (!sodium.methods.verify(Buffer.from(signature, 'hex'), Buffer.from(timestamp + body), this.publicKey)) {
+      return { status: 400, body: '' };
     }
     const data = JSON.parse(body);
+
     const result = await this.handle(data);
-    return JSON.stringify(result);
+
+    return {
+      status: 200,
+      body: JSON.stringify(result),
+    };
   }
 
   async handleFromGateway(data) {
-    await this.handle(data);
+    const interaction = new Interaction(this.client, data);
+    await this.handler(interaction);
   }
 }
 
diff --git a/src/structures/Interaction.js b/src/structures/Interaction.js
index 4c811c43..0d6ea0a1 100644
--- a/src/structures/Interaction.js
+++ b/src/structures/Interaction.js
@@ -50,19 +50,19 @@ class Interaction extends Base {
      * The channel this interaction was sent in.
      * @type {Channel}
      */
-    this.channel = this.client.channels.cache.get(data.channel_id);
+    this.channel = this.client.channels?.cache.get(data.channel_id);
 
     /**
      * The guild this interaction was sent in, if any.
      * @type {?Guild}
      */
-    this.guild = data.guild_id ? this.client.guilds.cache.get(data.guild_id) : null;
+    this.guild = data.guild_id ? this.client.guilds?.cache.get(data.guild_id) : null;
 
     /**
      * If this interaction was sent in a guild, the member which sent it.
      * @type {?Member}
      */
-    this.member = data.member ? this.guild.members.add(data.member, false) : null;
+    this.member = data.member ? this.guild?.members.add(data.member, false) : null;
   }
 
   /**
@@ -99,11 +99,9 @@ class Interaction extends Base {
 
     const { data, files } = await apiMessage.resolveFiles();
 
-    return this.client.api.interactions(this.id, this.token).callback.post({
-      data: {
-        type: InteractionResponseType.CHANNEL_MESSAGE_WITH_SOURCE,
-        data,
-      },
+    return this.client.api.webhooks(this.id, this.token).post({
+      auth: false,
+      data,
       files,
     });
   }
diff --git a/src/util/Constants.js b/src/util/Constants.js
index 0af65b3a..9eeb4147 100644
--- a/src/util/Constants.js
+++ b/src/util/Constants.js
@@ -700,6 +700,7 @@ exports.InteractionResponseType = {
   ACKNOWLEDGE: 2,
   CHANNEL_MESSAGE: 3,
   CHANNEL_MESSAGE_WITH_SOURCE: 4,
+  ACKNOWLEDGE_WITH_SOURCE: 5,
 };
 
 function keyMirror(arr) {