Beating Contra 3 on Hard mode without dying a SINGLE time!
Going through Kaizo Mario without dropping a single F-Bomb.
He went through the sequel as well, without a single F-Bomb. He even found a glitch that could have made traversing a level so much simpler, and what does he do? Jump off a cliff to cancel the glitch out, so he can play Kaizo Mario fairly.
His trouncing of the notorious Labyrinth boss in Sonic the Hedgehog The Porcupine The Guinea Pig. Not to mention that (apart from once when it was necessary to avoid drowning) he took no damage in the entire game.
Playing through an early version of a retranslation of Final Fantasy IV that had a glitch he didn't know about in the first Tower of Babel segment, where Yang performs his Heroic Sacrifice but the game never takes him out of the party (therefore the Event Flag is not set and you are unable to proceed any farther into the story), pretty much invalidated his entire playthrough. What does Sir Ron do? He plays (off camera) through the entire game again up to that point, including LEVELING EVERYONE UP TO 99 AGAIN and then casually dismisses the catastrophe, and continues like nothing happened!
His entire Final Fantasy IV LP. Obtaining EVERY item possible along with maxing his characters Levels, HP, and MP.