Encountered what seemed to be a strange behavior/potential bug when attempting to kill Duke Searbrand in the eruption event for Season of Discovery. Playing Horde Druid on Wild Growth. When he spawns, an immediate attack would not tap him, but an attack about a second later from others seemed to tap it for Alliance. In my situation I am horde hitting Duke with a rank 1 Moonfire and, without fail, even if (as far as I could tell) I hit him well before any other player, alliance or horde, it would start off red (tapped by me) and then a second later become grey (tapped by others). It seemed oddly consistent for alliance getting the tag over any horde in the area. No horde in the area were able to tag and kill him until all Alliance had moved on. About 4 groups of Alliance characters came and went, getting the tag and killing Duke each time with the same delayed tag being observed each time. Could just be coincidence but I’ve never run into mob tag behavior like this before.
I’m seeing the exact same behavior you described but as an alliance warlock using instant searing pain. I very clearly got the hit before anyone else, saw the hp drop,and then about a seconnd later an orc hunter ran up and hit it and the tag swapped over to him