Algodoo

This is my first battle! Whoever can get their opponent to collide with the black killer rectangles will get a point. First to whatever amount of points you decide is the winner. If you're Luma, press left and right arrow keys to move. Up to jump. Same goes for your opponent. Press A and D to move. W to jump. Each player is 20.00 speed acceleration. To add points, double click the scoreboard with your mouse or cursor pad, go to text, and add 1 point to whoever knocked their opponent on the black killer walls. You can make your own character, either on the web, or just by using the tracer. Just keep your character to 20.00 acceleration. And add your player's name by following the same steps shown to add points. Just don't add a point. Go to the names above the number 0 and change the name to your character's name. Also, Mermaid Rosalina is the judge.

Update 1: Added invisible blocks so your character can't escape.

The End!

P.S. You can play Rocket League mode by setting a timer on your phone for 5 minutes.