Another idea for DMs: If on a Move Action the fighter marked NPC was stopped due to a successful opportunity attack, doesn't mean it can not Charge (confined by the rules) as per their Standard Action.
Fighters may mark anyone they attack. This includes attacks not taken on their own turn, such as opportunity attacks and Combat Challenge attacks. So in this example, the fighter marked the moving creature.Doesn't that assume that the fighter doesn't have something else marked? Or can the fighter mark many things just each creature can't have more than one mark? I haven't looked at this part for awhile since we haven't had a fighter in the group.
Effect: Whenever an enemy marked by you is adjacent to you and shifts or makes an attack that does not include you, you can make a melee basic attack against that enemy.
Correct.Ok...I'm just mixing up the features.
So Combat Challenge lets you get an Melee Basic Attack under (conditions) as long as you already have it marked. Being an immediate interrupt this can only be done once per round.
Combat Superiority improves your OA's with a bonus to hit and stops movement IF that is what caused the OA in the first place.
Combat Challenge and Combat Superiority do not combine as Combat Challenge is not an OA it is specifically a "Melee Basic Attack". Feats that add to OA do not improve CC for the same reason.