This was a pretty easy chall, we just need to hack a javascript game. I think however it is interesting to post a writeup as a lot of different solutions were possible and it is engaging to see how people solved it.

Here is mine:

setInterval(function() {for (var i=2; i<gamé.currentScene.childNodes.length; i++) {gamé.currentScene.childNodes[i].direction=0}}, 10);

Basically after starting the game I change the direction of every enemy bullet to go in the other direction (i.e.: to the right) instead of hitting my spaceship.