diff --git a/packages/models/quest.js b/packages/models/quest.js
index 84c1966..bb4ca73 100644
--- a/packages/models/quest.js
+++ b/packages/models/quest.js
@@ -10,6 +10,25 @@ const responseSchema = new Schema({
   color: String,
 })
 
+const fileConditionSchema = new Schema({
+  path: String,
+  type: String,
+  exists: Boolean,
+})
+
+const conditionSchema = new Schema({
+  command: [String],
+  output: [String],
+  error: [String],
+  pwd: [String],
+  files: [fileConditionSchema],
+})
+
+conditionSchema.add({
+  OR: [conditionSchema],
+  NOT: conditionSchema,
+})
+
 const stageSchema = new Schema({
   id: {
     type: String,
@@ -29,12 +48,7 @@ const stageSchema = new Schema({
     required: true,
     default: false,
   },
-  condition: {
-    command: [String],
-    output: [String],
-    error: [String],
-    pwd: [String],
-  },
+  condition: conditionSchema,
   responses: {
     type: [responseSchema],
     required: true,
@@ -52,18 +66,6 @@ const Quest = model(
     title: String,
     order: Number,
     instruction: String,
-    tasks: {
-      id: String,
-      content: String,
-      display: {
-        type: Boolean,
-        default: false,
-      },
-      completed: {
-        type: Boolean,
-        default: false,
-      },
-    },
     stages: [stageSchema],
   })
 )
diff --git a/quests/helloworld/game.yml b/quests/helloworld/game.yml
index 5a3be6a..c9e7fb7 100644
--- a/quests/helloworld/game.yml
+++ b/quests/helloworld/game.yml
@@ -168,8 +168,9 @@ stages:
     condition:
       pwd:
         - '^/home/commander$'
-      include:
-        - !*.txt
+      files:
+        - path: '*.txt'
+          exists: false
     responses:
       - type: dialogue
         speaker: Unix 精靈
@@ -178,7 +179,7 @@ stages:
           - 請使用 `rm [檔案名稱]` 來銷毀垃圾。
           - 這個 `rm` 指令也可以一次處理多的檔案喔，用法跟 `mv` 一樣。
           - 如果你忘記的話，看看這個範例：`rm [檔案名稱1] [檔案名稱2]`
-scroll
+
   - id: remove-trash
     task: 銷毀垃圾
     repeatable: false
@@ -187,8 +188,9 @@ scroll
     condition:
       pwd:
         - '^/home/commander$'
-      include:
-        - !*.trash
+      files:
+        - path: '*.trash'
+          exists: false
     responses:
       - type: dialogue
         speaker: Unix 精靈
@@ -248,7 +250,7 @@ scroll
       - type: dialogue
         speaker: Unix 精靈
         content:
-        - 現在，你可以使用 `cd ..` 來回到上一層目錄。
+          - 現在，你可以使用 `cd ..` 來回到上一層目錄。
 
   - id: exit-bookcase
     task: 離開書櫃
@@ -282,4 +284,3 @@ scroll
       - type: narrative
         content:
           - 你踏出了房門，真正的冒險現在才正要開始。
-          
\ No newline at end of file