A Crossover Villain-In-Chief is a previously established villain that, for whatever reason, becomes either the official or de facto leader of most or all of the other villains in the crossover. There may be a clear reason why they were raised to this position: they may be the most intelligent and/or best strategist, they could have the best (or only) leadership skills of the group, they may be the most skilled in combat, or they may just be so scary that none of the other villains dare challenge them. Sometimes, however, they may become the leader for no other reason than being the most popular villain, or even the writer's favorite of the bunch.