Mission 1: The Cleaner
In the first mission, after getting the assault rifle you'll have to hold off enemies while your robot opens a door. Do not shoot the door panel to close the door behind you. Once the enemies make it to you, use the drone to shock them (Triangle/Y). You can restart the checkpoint if it fails.
Here is a video guide with English commentary!
Here is a playlist of guides for this game!https://www.youtube.com/playlist?list=PL-HeW6XkKdULGSVKoX6Iu...