Tabula Rasa

In the room just before the stairs to Forgotten Experiments there's a tank off to the left right here on the map. Clicking the tank will release Nutraal and he'll run up the stairs into the boss room to wait for you.

Once you pull, Nutraal will take it upon himself to run a marathon before you kill the boss, and the guy does not stop running for more than a few seconds at a time. While he's running around you have to hit him 3 times with the signature abilities of each of the bosses. It becomes easier to hit him if you keep him marked as well.

In P1, hit him with Rending Charge by keeping him in the white arrows between people that get picked.
In P2, get him hit by the swirlies that spawn from Volatile Spew. Since he runs around and they bait onto players, your best bet is to have your group surround him and run with him during Spew.
In P3, bait the Deep Breath onto him. He can run between quadrants so you might low roll but since there are only 2 Deep Breaths per cast anyways you'll need 2 casts to get him hit 3 times.

As you successfully hit him, he'll gain stacks of the following buffs.
P1 - [spell=411116]
P2 - [spell=411117]
P3 - [spell=411118]
Use these debuffs to track your progress and don't kill one of the bosses until their debuff is stacked 3 times.

If you need help with the metas feel free to add me to Btag (NA only) or Discord!
Btag - FrostyShot#1667
Discord - yarini

Other than feeling like a complete tool for what you the player do to poor Nutraal, Easy Fun Solo Achievement for Level 80-100 Worldsoul Saga & beyond...

1. Normal Difficulty.

1b. Handy raid achievement tracker can be enabled which will turn from red to white once all criteria met.

2. Head back down the steps leading up to the boss area and pop open the tank along the wall, letting Nutraal head up to the boss area.

3. Begin fight, don't kill boss.

4. Neldris primary attack, Rend, will be the arrow charge that must hit Nutraal. Position yourself on or behind Nutraal for him to get hit. Do it 3 times.

5. Criteria has been met, kill Neldris.

6. Now, Thadrion shows up and his primary attack, Slime, must hit Nutraal 3 times. This one was a lot quicker than the first. Kill Thadrion.

7. And here's Rionthus. His primary attack, where he swoops across the room must hit Nutraal 3 times. Position with Nutraal in the center of the room preferably.

8. With all criteria met and red has turned to white in the tracker, kill Rionthus.

9. ?

10. Profit. Achievement Completed.

why are we tormenting poor Nutraal?