JavaScript meets the arcade.
http://www.nintendoworldreport.com/hands-on-preview/36915/xtype-plus-hands-on-preview-at-gdc
XType Plus is a bullet hell-style shoot-'em-up that features wave after wave of bosses. The bosses are procedurally generated from a small set of parts, and increase in complexity with each new round. Your mission is simple: avoid the projectiles (which include bullets, missiles, and lasers) and take out the core to destroy the boss.
Originally designed as a Chrome experiment, XType was ported to mobile platforms. Though you can technically play the game in the Wii U web browser, performance isn't optimized there, and it runs very slowly. Through the Nintendo Web Framework, the game plays at a blistering pace in HD and uses a twin stick control scheme.
The second Nintendo Web Framework game to arrive on Wii U (after Blok Drop U), it utilizes the Impact JavaScript game engine, and provides flashy lighting effects and online leaderboards.
And the plus version adds a new time attack mode. Time bonuses are added when bosses are defeated and time is subtracted when your ship is hit. The mode also adds a limited super-weapon to help you get out of tight situations.
XType Plus is a simple game, but it’s simplicity is also its virtue. The game was quickly adapted to Wii U and its endless rounds provide an ever-increasing challenge.