Never played it!
On CoD, if you player regular team death match its much more run and gun, but out clan is purely hardcore, which means its minimule damage so easier to die, team kills on (so you can random grenade) and its just generally much harder as you have no UAV's (maps)
Once you get it, let me know and we'll trail you, its a clan rule, but you'll get in regardless of skill. Just need to show your activeness.