OOC: What the Hell did I get a negative 3 modifier for. I guess revenge for delaying the turn? >_>
Also, TPK incoming? 3/6 players infected with constant HP drain and debuffs, which somehow are much more powerful than any of my spells have ever been. I guess it's all on me for using my poison magic. Which makes the point of poison magic really stupid, if I can't use it in combat without killing everyone...
-2 spell level, -1 lack spell knowledge. Incidentally, I hate how clunky that last one is and will probably replace known spells with mastered spell principles, so instead of learning Fireball and no longer taking a penalty to fireballs you learn Flaming Projectiles and no longer take a penalty to fireballs, fire darts, fire bolts, fire lances, fire wheels, or whatever else you can think of that doesn't require some additional principle. Possibly with spell levels attached, ie Fire Projectiles L2 would remove the -1 for level 2 fireballs but not level 3 ones.
Screwups being more powerful than successes has always been kind of a thing, and it's true for all magics. Like when Ochita one-shot himself or wolfchild permanently blinded himself, neither of which was likely to happen to a serious enemy at that spell level. In the case of your slime, of course, there was also the added nastiness of having it combined with Ochita's magics.
On the subject of a TPK... yeah, I'm a bit concerned here. Part of the problem is that the nautili can field one attacker for everyone near the door, which is almost everyone at the moment. Part of the problem also seems to be that you're getting low rolls, though that might just be an illusion.
That said, a daring escape or reversal isn't impossible.