Tanks, please figure your shit out. You're the leaders of the group. It's part of the job. Its not mere arbitrary social standard, it's a game mechanic.
You control where mobs stand. Put them in the right place. Onyxia phase 1 should not be done directly in the middle of the room 45 degrees to the left. Get against the fucking wall and get her straightened out. This applies to all other cleaving, kknocking back, AoEing, or whatever-other-bad-thinging mobs.
You control where DPS stand. They're a lot like NPCs. They do not move unless they start getting out of range errors. But once they're out of range, they tend to move. If there's a pat that you want them to avoid, you'd better drag the current mob until the DPS must move. If not, you're getting adds. Blame the DPS, it's their fault, but c'mon, you're the baby-sitter. Pick them up and put them back in their seat and make them eat dinner instead of playing Outlet Explorer. They tend to lose that game. So let's say you're in PoS and you're pulling the ghosts near the end and trying to avoid that one pat. The shadow priest is still standing way back and will aggro it. Just keep running down the hall until he is out of range and must run to catch up.
Fun fact: Red-haired people are more resistant to electrical shocks than others, but we sunburn more easily too. This might be how my brother survived childhood.
Yes so, know the fight. Everything about it. Know when DPS need to stop and figure out a way to make it happen. Drag the mob all over, BoP the melee, pop DS so they die. All is fair when teaching DPS to stop DPS.
[late addition] The true reason we cannot have nice things is that if I write after midnight I get mixed up by the date change and schedule the post a day too late.
Important PSA: Don’t eat the worms!
3 hours ago