diff --git a/CHANGELOG.md b/CHANGELOG.md
index 614d50d0f..a06780b10 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,6 +1,17 @@
 ChangeLog
 =========
 
+4.0.0
+-----
+
+オセロがリバーシに変更されました。
+
+### Migration
+
+MongoDBの、`othelloGames`と`othelloMatchings`コレクションをそれぞれ`reversiGames`と`reversiMatchings`にリネームしてください。
+
+You need to rename `othelloGames` and `othelloMatchings` MongoDB collections to `reversiGames` and `reversiMatchings`.
+
 3.0.0
 -----
 
diff --git a/package.json b/package.json
index c5092e6f1..bd5dc8e84 100644
--- a/package.json
+++ b/package.json
@@ -1,8 +1,8 @@
 {
 	"name": "misskey",
 	"author": "syuilo <i@syuilo.com>",
-	"version": "3.1.1",
-	"clientVersion": "1.0.6528",
+	"version": "4.0.0",
+	"clientVersion": "1.0.6535",
 	"codename": "nighthike",
 	"main": "./built/index.js",
 	"private": true,