I finally manage to beat MM3 using only the mega buster, ignoring a few necessary exceptions. I also don't use any E-tanks or die in this run.

The real tough parts were Doc Wood, Quick, and Flash. They are all very much harder than their Mega Man 2 counterparts, and allow little room for error when fighting with the buster. With Quick Man, it's good to let the boomerangs hit you. 2 damage is much better than losing a quarter of your health from a body collision.

It's a pretty solid run overall, but I get sloppy at times. Even the Yellow Devil almost managed to kill me. Anyway, enjoy.

No save states, slowdown, turbo, blah blah.