After reading about this mod on TV Tropes, I definitely think
Facciolo could have some fun interactions with my OCs…
For
the Belnades sisters, he'd taunt them by bringing up how he had a conversation with a purple tie-dye hedgehog who
really wants them dead, which all four would recognize as being their archenemy, Mysto Majora Kijadhimov (yes, the middle name/clan name is a
Majora's Mask reference, for those who didn't notice). Cassandra and Flora would still be confident that they could take him down (after a moment of panic in Flora's case), but Annie and Sonja would probably need half a minute to regain their composure.
In Garcia's case, Garcia would just call
Facciolo out for his mindgame/body-jacking shenanigans and declare his intent to fry him. If Garcia's in co-op with
Marine, however, Marine's conversation with
Facciolo would take precedence, and once
Facciolo starts making death threats against Marine, Garcia would freaking lose it and make Flamberge-esque threats to scorch
Facciolo so thoroughly that
lava would seem cool compared to him. (Garcia has a huge crush on Marine, FYI.)
Legault would just state his intent to bring
Facciolo to justice for his crimes.
This is all just conjectural; I dunno much about this
Facciolo, so I have no idea what he'd say.