You may change it to any of the supported languages.
<How to change language>
1. Select the Menu (≡) on the top left of the game screen, or press the "esc" key on your keyboard to open the menu
2. Select "Options."
3. Select the very bottom icon on the left side menu to open the "Language" settings and select the language you want
Supported languages:
Japanese, English, Simplified Chinese, Traditional Chinese