Stuck in the end

Hi,
So I've basically travelled to the Wasteland island and gone to the Dark Castle. I talked to Gatekeeper and went out of the castle and got ambushed by Mysterious Man's orc army. My race is derth and I use magic as attacks. I kept spamming the orcs with thunder storm. I ended up with wasting money for healing and mana potions and eventually ran out of both cash and potions. :/
Unfortunately I didn't save just before arriving to the island so is there any way of getting out of this situation and kill all the orcs?
Edit:


Gold: 1461
So I've basically travelled to the Wasteland island and gone to the Dark Castle. I talked to Gatekeeper and went out of the castle and got ambushed by Mysterious Man's orc army. My race is derth and I use magic as attacks. I kept spamming the orcs with thunder storm. I ended up with wasting money for healing and mana potions and eventually ran out of both cash and potions. :/
Unfortunately I didn't save just before arriving to the island so is there any way of getting out of this situation and kill all the orcs?
Edit:


Gold: 1461