Play Bangai-O Spirits (XenoPhobia) Online

Bangai-O Spirits came out on the Nintendo DS in 2008, developed by Treasure. It was a time when the DS library was full of experimental titles, and this one fit right in with its focus on pure, unadulterated action. You don't get many games that play like this, even now.

You control a small, agile robot, moving screen by screen through abstract stages filled with enemy mechs and turrets. Your main goal is simply to survive and clear each area, which often means wiping out every opponent. The signature mechanics are the EX attacks, which let you fire hundreds of missiles or lasers at once, filling the screen with your own projectiles and enemy bullets. You also use a close-range sword and a reflector shield to parry shots back at foes. The pacing is frantic, and the difficulty is brutal; one wrong move and you're surrounded, then instantly vaporized. It feels like solving a violent puzzle at a thousand miles per hour.