Are you looking to Speedrun Batman: Vengeance?
One of the most essential tricks to learn when speedrunning Batman: Vengeance is the Invincibility Glitch. It can be difficult to pull off, and the community is still trying to figure out how to pull it off even more consistently, but if you can nail it quickly during your run it will make the levels where it’s applicable go so much quicker!
Hopefully, this tutorial video is useful. For this, I’m specifically running the game for the Gamecube version and all of the footage you’ll see is taken from playing in Dolphin Emulator. I have tested the glitch on the actual Gamecube and a Wii, but have yet to confirm it’s viability on the other versions of the game.
You can theoretically achieve this glitch with any damage source that outputs a constant stream of damage to Batman, such as the fire from Joker Jack in the Boxes or the frozen air in the Freeze levels, as you’ll see in the video. However, this has the potential to brick the game in certain spots so you have to be careful.
So far, we know that if you don’t pick up a health pack before fighting Mr. Freeze you won’t be able to complete the fight, and if you try the invincibility glitch on the Laughing Gas Inferno level before any of the cinematics, you will also get stuck. For some reason, getting a health pack in Laughing Gas Inferno won’t help you pass the cinematics without bricking like it will with the Freeze fight and cinematic. There’s got to be something going on with the code there I don’t understand!