I've heard about Crocune, Crobro, and Crobat. (OK, so maybe Crobat doesn't belong.) I know it means CM + ResTalk + One Attack, but is that the origin of the name? And would a Bulk Up + ResTalk + One Attack fall under a "Cro" set?
The "Cro" prefix comes from a Battler named Cromat who was famous for using RestTalk sets. So really as long as it has resttalk its a Cro set I guess.
Source: Knowledge