Cập nhật lần cuối vào 2019-02-28

1. The bullets will hit back the enemy, adding a slight screen shake for shooting.2. The mission mode is extended to the tenth chapter3. Increase difficult mission mod, the fighting will be more intense now.4. Fixed the the bug of the venom gun which value shows too fast and leads to flashback.5. Fixed the bug of using skills when entering the portal, which may cause to no attacks.6. Fixed the bug of the novice tutorial.7. Many improvements have been made to other aspects of the game.