Battle Kid: Fortress of Peril may look old, but it's actually released in 2010! Mainly inspired by the PC game I Wanna Be the Guy, this game is classic platforming action, where anything can kill the player in one single hit. While it's not unfair (as opposed to I Wanna Be the Guy), it's still really hard.
In this run, Aglar and Fortranm use a password provided by the game once it is beaten to access the secret level named "Petunia X" (slightly modified and renamed "Golden Fort" in the Japanese release) and beat it as fast as they can.
Watch this run being played back on a real console.