Play Matrix Ninja Online
Dodge falling spikes as a green block in this simple Flash game, testing your reflexes and aiming for high scores with each run.

Note: Right click and select full-screen for best experience
Matrix Ninja is one of those stupidly simple Flash games that somehow hooks you. You're just a green block dodging falling green spikes—sounds basic, but there's something weirdly satisfying about it. The first time I played, I went straight for Hard mode and got wrecked in like three seconds. Turns out starting on Easy isn't a bad idea.
Controls are barebones (arrow keys only), but that's the point—no fluff, just pure reflex testing. The green-on-green aesthetic gives it this retro Matrix vibe, even if it's probably just because the dev kept things simple. After a few runs, you start seeing patterns in the chaos, and that's when it gets dangerous. "One more try" becomes five more.
It won't change your life, but it'll kill 10 minutes better than most mobile games today.