You can learn The Great Leveller and later upgrade it to The Greater Leveller in the Grand Conjuratorium, in Hubble. This is entirely optional and only the main hero will learn this spell.
Warning: this guide contains minor spoilers for Dragon Quest VII.
Learning the Great Leveller
You can learn the first spell when you finish the main questline in Hubble in the past.
Before traveling back to the present, head to the Grand Conjuratorium and speak to The Wiz, on the second floor of the main building. He’ll tell you about a spell he wants to share with you, but he needs to finish it first.
He won’t do it as long as you stay in the past, so walk back to the portal and teleport to the present.
The new Hubble Island will rise on the northwestern corner of the map. Head there and enter the Grand Conjuratorium.
You’ll need to do a cross pattern in the main building, starting on the western side, at the wizard statue, then exiting through the eastern opening, and then going from the north opening to the south.
If you do it correctly, you’ll unlock a path to the staircase in the center.
Enter this basement, collect the Mini Medal and the Green Fragment in the room, and open the door to the next room
This next room has many tombstones. Examine the biggest one, and after reading the message left by The Wizz, your hero will learn The Great Leveller.
Only the main hero can learn this spell. It costs 15MP and it removes Sap, Buff, Kaclang, Puff, and Megamorphosis from any enemy. This instant debuff can be very helpful against some later bosses.
However, this spell can be upgraded once more…
Learning The Greatest Leveller
Warning: there’s a game-breaking bug with the second part of this quest. If you talk to The Wizz with Maribela in your party, she’ll disappear and you won’t be able to choose a fourth member for your party, making you unable to progress. Don’t do this quest with Maribela in your party. Either do it before having Maribela again with you, or put her on the reserve before doing this quest.
You can learn the second part of the spell after you recruit Aishe for your party.
After you get her, travel back to Hubble in the past, and head for the Grand Conjuratorium.
Talk to The Wizz once again, answer “no” on the first prompt and “yes” when he asks you to show him the spell. Upon learning that you already mastered the spell, he’ll begin to work on a newer, stronger version.
After this cutscene, get back to the portal and to the present time. Zoom to Hubble and enter the basement of the Grand Conjuratorium. You’ll need to do the puzzle again to enter.
Read the tombstone again and your hero will learn The Greater Leveller.
Congratulations! This upgraded version not only removes all the previous stats, but it also removes Oomph, Bound, and seals ALL spells for 2 turns. However, now it also affects everyone, including your own party. It’s also more expensive to cast, costing 20MP.
If your party is more oriented towards physical attacks and abilities, this spell can make some magic caster bosses a cakewalk, as they’ll be blocked from all spells and your party won’t suffer as much from that effect.