Spewer is a bluntly-titled puzzle platformer from Edmund McMillen, currently hosted by Newgrounds.
You take control of an adorable little sprite blob presumably named Spewer (dubbed so in a way similar to Slimer being called Slimer). He’s a test subject in some lab where they breed vomiting blobs, feed them random shit, and then see what happens.
Did I say vomiting blobs? Of course I did, as retching is the primary mechanic of Spewer. Sure, your blob can wiggle left and right and jump through the air. But if you want to make it past those spikes or get an extra few feet off the ground, you’ll have to puke your way to success.
Assuming you can figure them out, the individual levels go by quick (good thing there are tons of them). If you can’t quite get grasp them or execute correctly, the levels crawl by (bad thing there are tons of them). However, you have only your ineptitude to blame if it feels stale. Spewer mixes up its own formula by changing your puking abilities depending on what items or food you consume. I won’t ruin anything for you (and I must confess I’ve only scratched the surface of this one), but let’s just say your vomit’s properties change as quickly as the wind.
You can try it in browser if you like, but sputtering PCs (like mine) may benefit from actually downloading the executable. I’m sure that will make Mr. McMillen feel all warm and fuzzy, too.