This trick saved my life when I was several levels short of fusing Trumpeter for the final boss.
Also, there's no real satisfaction to be had in cheating your way through a difficult game.
Needed -And don't use save states next time you play a game. Relying on them too much in an RPG means you'll always be underleveled, which means you have to keep abusing them to progress. Eventually, you'll always end up in the situation you're in right now. Same thing applies to action games: Your skills will never improve if you keep using save states, so as the game gets more and more difficult, you'll end up using more and more save states to compensate.
Persona that Nulls/Repels physical
Null Rage (VERY IMPORTANT)
Weapon with low crit rate and enough attack power to 2-shot babies (no bats/reaper weapon)
Optional -
Stat-boosting armor/EXP raising armor.
Strategy:
1. Encounter Pringle King x2 (harder than it sounds)
2. Kill off party.
3. Wait for babies to be summoned.
4. Target 1 baby with regular attack
5. Hit triangle
6. Do whatever for8 hours20-25 minutes.
7. Revive team
8. Kill kings.
Also, there's no real satisfaction to be had in cheating your way through a difficult game.