Be careful when learning Pandora's Box. If the first Dragon Zombie you meet in the right path doesn't cast it as a final attack, a glitch seems to prevent other Dragon Zombies on the right path from casting it. However the Dragon Zombies in the central path apparently cast them fine.

Also you can combine the effects of spells in useful ways:

You can make learning Roulette easier if you first learn Death Force and cast it on both the party and the Death Dealers. No matter who Roulette hits, no-one dies and you can keep going until everyone in the party has learned it.

Also Death Force may make the item Kiss of Death actually useful. Normally it wipes out all monsters along with the party. I'll have to see if Death Force can protect the party from it's effects.