It was simply this, most things could be used by anything, like I can play SCH while having fire III.

THM and CNJ used to be able to use shield abilities. It would be like if you leveled PLD now, and unlock sentinel, you could use sentinel on THM and CNJ just as long you had a wand/shield combo. There was a move called phalanx I think, it did not last long but if you took a hit, no matter how strong it was, it healed you not damage you.

Then there was the broken spike spell for THM, shock spikes or something. So say you had a leve to do while noticing it is not possible to clear because level 10 for one leve was not the same difficulty as a level 10 for another, so you really did not know how hard leves where unless you memorized them by name. So you have this leve with the cactus things that are not possible to kill for your level while the special move oneshots you. So what do you do? Use the spikes spell and hope it uses the needle move before the ability wears off. If it works, you just made the monster literally kill itself killing you. It was sooo broken it was hilarious .