You Can't See Me

When the boss does his [spell=444363] frontal and sends people into the downstairs phase, you can find these slimes around the far edges of the room. I don't have a map for them, but they spawn in the same locations every pull, and there are enough for everyone in a 30 man group, though the last few people might be hunting them down. They cannot be targeted using a macro and can only be seen while down below.

For the achievement everyone in the raid needs to step on one while down below and then live until everyone has the debuff. Once everyone does, you need to stack up. Doing so will remove everyone's debuffs and then a few seconds later a Volatile Ooze will spawn which you just need to kill. It didn't appear to have any mechanics and we killed it pretty quick. Once it dies you can kill the boss. The text on this achievement is slightly misleading so make sure you kill the add first.

There's no real rush to get everyone Slimed if you're willing to hold boss DPS. We used 4 total slime phases (2 per group) for safety but you may be able to get it done in 1 per group. You can also survive going down in back to back groups with a personal so if you've only got 1 or 2 more people and they went down on the last one, you can send them down again. I'd also recommend when you go down that you kill the adds first, then spread out to get your slimes. If you don't it creates a lot of raid damage for your healers to deal with while people are extremely spread out getting slimes, and with how far away they are it's pretty difficult to get a slime and still get back to the adds before your debuff falls off and you get pulled back up top.

Lastly, if you've already got your slime you can still help people down below find one and either ping it or drop a world marker on it for them.

If you have questions about the metas feel free to add me to Btag or Discord!
Btag - FrostyShot#1667
Discord - yarini

Important information for smaller groups: you NEED to be 10 players minimum, else the add won't spawn!

Just had a person in my group die after getting the slime. We all tried to stack on the dead body, but the add did not spawn. Guess we need people alive to stack to get the add for the achievement