Group size varies a bit, but the kill was with fifteen; fewer than that may possibly be a problem, I'm not sure quite if players have more ability to shift the runes in a smaller group to compensate for the lower numbers.
It basically boils down to:
P1: Fight the adds entirely on one side (we used the right, FWIW), using that side's pillar for the reveal/hide mechanic; try to keep all goo safely on that side. We didn't bother with tank swaps, careful cooldown usage seemed to be enough to weather the storm of the freeze.
P2: All stack in the middle, put Azshara so she's draining the middle rune as well, and run out individually when you hit five-ish stacks, then do not touch the rune again until you've lost the debuff; stay with the middle when Reversals move things around. Use the left pillar or the console to hide from the big AOE. There's much less movement, and there's a
reasonable chance that you'll get the Reversal to helpfully bring a drained Seal over to you to help recharge it
P3: Because you're based around the middle, you can block LOS from the casters on the runes, and don't have to worry about breaking the shields; you can just splash down the myrmidons.
P4: Move out of the middle when the big black hole's about to turn up, and be alert to the beams that will cross the middle; tanks shift around a little so one tank can devote themselves to handling the console. I'm not quite sure how the swap-everything Reversal rebalances things, but it felt like runes were perfectly safe.
We didn't involve the tanks heavily with the draining - I think each of us did one drain, and not a full-size one - so you might possibly need to do a little bit more yourself to make up for the number differential, but if the fight scales around group size in
that way, that won't be an issue.
We didn't do anything particularly unconventional - as far as I'm aware - on the transitions.
If it's any use,
here's our logs.
