First of all, this is just a joke, and is not meant to be taken as a major lore clue or something. Second, I discovered this messing around with the original line. Turns out, the phrase “I always came back” backwards sounds like “I’m Muxxy Awarp now.” Muxxy Awarp sounds like Mucky and Warped, and, well, Scraptrap IS Mucky and Warped! It’s a coincidence, but a crazily accurate one!
Scott Cawthon for FNAF, PJ Heywood for Scraptrap’s “I always come back” line, and all of Scraptrap’s other voicelines.