Hint: Buy diamonds at Darkwood, and sell them at Niato. You get 1000 profit each. When going back to Darkwood, buy coal from Niato and get it to Darkwood To get about 20 profit each. For this plan to work however, you need a lot of cash to buy the diamond from Darkwood.
Tri-guardian was very hard. I can't believe that its weapons can be so devastating. Anyways, i beat it after evacuating 2 times to regain strenght and with fighter #3.
I just love the hardcore mode. It makes playing need even more strategy, as you have to know your powers, and the enemys powers. The risk taking makes death of full party hurt a lot. That is very smart.