Cold Shell is a top-down, sci-fi, arcade brawler with persistent RPG elements. Bash thugs and change wallpapers.
Hi there.
It normally takes 3 to 11 tries to defeat tutorial boss.
Here's a pro tip: facing the boss, hold your shield up (Right mouse button) it will reflect bullets back at the boss and deal damage. When your stamina is almost out click Left mouse button for a shield charge at the boss.
It will either kill the boss or leave it with a tiny bit of hp left.
Also heal (E button) often. There is no mana, only cd. So don't save it.