I DUG THROUGH TO THE OTHER SIDE OF THE LAVA CORE!!! You have to do the dig on one of the sides and jump from the top of the lava. But you can do it too! Also, that could of been a hard badge.
On nightmare: Healing skills COMPLETELY USELESS!, Your characters are GONNA DIE, if you don't get a lucky in the corner ranged guy you are SCREWED! Seriously buddy, why are the monsters AWAYS faster even when you have a high chance of going first?
And don't even get me started on the 0 on the dice rolls...
The only level that is near impossible is level 20. It relies way too much on luck. Now if the cave was moved back about two squares or so, then it could be less luck driven. Otherwise the terror spell is going to take up all your mana.
I've played this on armorgames, even beat the pirate ship there. I will say that due to no big advertisements here at kongregate the game runs more smoothly. Though I would still like a quality button.