In Radiant Garden, Ignis Fatuus has called a meeting between several of the villains he's met: Dani, Rikka Masami, and Jonathan Crane, also known as the Scarecrow.  There is, of course, the usual posturing between most of the villains.  He explains to them his plan of creating a group, one where the villains can band together and become stronger through sharing of resources.  All agree, and they decide to name this group the Collective.