The clan should already be signed up for the challenges and ops...however, not alot of ppl in the clan, besides myself and a few others, are core players. I prefer to play the game the way it was intended, but that's me. Most others play hardcore, BUT, there's a glitch in their system. As long as you're playing the right gametype, it doesn't matter whether the kills/confirms come from core or hardcore, their system counts them.