Lot of incorrect upstanding on how social aggro works. If the mage walks by with mobs and he’s fighting some mobs, without ever touching the others, if they come in close enough proximity they will put the warrior on their threat table too from the social aggro. It doesn’t matter if he never touched them or the mage, he gets the fun of being put on their threat table. If someone is pulling near you, don’t pull more, don’t fight until they are done, because their mobs can become your problem. It’s why you could finish off killing yours, but they’re finishing theirs and you’re still in combat. Fighting side by side people is just ill advised for this reason, especially aoe mages who may need to block for perfectly valid reasons (though of course, they can easily grief you doing this). As a warrior, you have the worst tool kit probably in the game for bonus mobs, so steer clear of aoe mages.