I don't know if this applies (never suggested a Crest before), but, how about one for Parasect where it can hit Ghost-type Pokemon with Normal-type moves and/or use any Spore-based attacks in Grass-type Pokemon. I'm using a Parasect in another fangame as a "capturer" Pokemon, since it can learn False Swipe, Spore and Stun Spore. But, since False Swipe is a Normal-type attack, I struggle against Ghost-type Pokemon. Would be nice to be able to have a capturer Pokemon without having to worry about Ghost-types like that.