After someone guesses them all correctly, I'll put in the download links.
It ain't TF2.
Confirmed as Gang Garrison 2.
Yeah, I can definitely remember playing as...a sweater...with a thing in the middle of this town...
Confirmed as An Untitled Story.
Heyyy, it's Ogmo! Remember him? Nope? TOO BAD.
Confirmed as Jumper 2.
The game comes with two pre-made levels. The REAL levels are user-made.
Confirmed as Knytt Stories.
Mario Vs. Reimu? NO WAI.
Confirmed as MUGEN.
Before you ask, no, this is not Super Smash Bros NES.
Confirmed as Super Mario War.
You're not a real gamer if you get this wrong.
Confirmed as Cave Story.
C'mon, this is an easy one!
Confirmed as N.
Kirbies? With GUNS? Now I've seen everything!
Confirmed as Teeworlds.
This game isn't everything it seems. It slowly reveals the truth...make it go away...please...make it go away.
Confirmed as Eversion.
This isn't super mario bros. It's more like a toned down version of a similar game. Seriously, when do mushrooms make you destroy EVERY brick on the screen, including ground? And bricks fall on you?
Confirmed as Cat Mario. (NOTE, THIS GAME IS NOT LIKE SUPER MARIO BROS IN ANY WAY.)
I hate this game.
I HATE this game.
I HATE this game!
I HATE THIS GAME!
I FUCKING HATE THIS GAME.
Confirmed as I Wanna Be The Guy.
Extend Left Arm.
Confirmed as Toribash.
A MOTHERFUCKIN' CITY.
Confirmed as ROBLOX.
The answer to life is a Rocket Launcher.
SPACESHIPS AND DANMAKU.
So yeah, post your answers and I'll put in the download links after someone gets them all right.