Don't forget
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also appeared on GBA and 3DS in Kingdom Hearts: Chain of Memories and the two Theatrhythm games.
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also had Dracula X on the Super Nintendo which was an inferior retelling of Rondo of Blood.
Well, Dante did appear in Project x Zone 1 & 2 both on the 3DS..in fact, the second game actually had him meet Chrom, Lucina, and Fiora, who's Shulk's friend.
This makes him one of the only 3rd Party characters to interact with a Nintendo character featured in Smash, along with Ryu, who was also in Project x Zone 2 and thus also met Chrom & Lucina, and Sonic, thanks to the Mario & Sonic series letting him meet every featured Mario, Donkey Kong, Yoshi, and Wario character. Bayonetta could also count if you count her having Bowser's limbs appear in attacks when in her Peach & Daisy costumes as interacting.
Geno may be a Mario character, but he's 3rd Party.