Cleared game in highest diff.

One warrior in front, cleric behind him.
Two hunters beside cleric.

Give warrior shield, and buff with armor and max his life. Make good use of his 'unkillable' ability, and only make normal attacks so you have power to spare.
Get the shield defense talent, it is needed sometimes. Nothing else is really worth to use in combat except maybe bloodthirst. For normal battles that arent hard a warrior can use the cleave ability or the increaced damage hit, but only use it when you got max power.
Dont give healing generation, cleric will heal warrior. warrior is so slow and takes so much damage that heal gen is pretyt worthless. defiance talent is his strength and for that he needs only power generation. Give power generation if you got some left over.

Dont give cleric a shield, use a censer for healing.
Buff clerics int, power regeneration and healing generation. Also get as much armor as possible.
Cleric rests all the time so he can heal.
Max power gen because of this. if you max your mana, and have power to spare then use the smite spell. it can be used to finish enemies off especially undead. get the -accuracy skill. it's good to have. if you did your group right, warrior should survive in order for cleric to cast this. just use defiance skill and wait for cleric to heal you.
warrior doesnt do much damage. rest instead of fighting if you are low on power and have a difficult fight ahead.
also get mass heal, it's needed sometimes. its very expensive though so don't use it. use only when you got several bad cases of poisoning or if the hunters are dying from spells or arrows.
use shield skill if you get a lot of mages and ranged attackers, then warrior can take all damage and give cleric a chance to heal all and hunters a chance to take out some ranged attackers.
get raise skill also. it will resurrect with almost max life if you max int. its no big deal if someone dies, even if the warrior dies. its bad if cleric dies. if both hunters die and you are having a hard time to get them up, run instead.

Hunters should use bow, max their dex. They are the guys who kill stuff in your team. Use the talent that shoots through enemies to kill. Nothing else is really reliable. Get poison damage items and enhancements, it helps a lot.
Armor for hunters is so bad that you can wear wizard items. Just make sure to get as many items as possible that give +health generation. This is because nobody will heal hunters unless its an emergency. Cleric is also not healed but has a lot better def. cleric also needs health regen, but power is most important.
Get the stun skill, its good against some enemies. its good against healers and it's good against acolytes and summoners who otherwise create bigger monsters. its even good against some bosses. try to kill minions first though, warrior is tough enough to handle a boss or two.
the skill to shoot many mobs seems nice but isn't. its very expensive and you often can't kill things fast enough for them to not do damage. use the penetration skill instead.

get an item that allows you to escape as a free action and give it to your tank. often spells and ranged attacks will kill everyone besides the tank and then he needs to run and survive. tank and cleric alone will die.
there is no good way to protect hunters, so just max health regen and have hunters kill anything that can attack them.

also dont forget inventory items. if youre blocked by a boss fight scroll past him. remember to rest upstairs when you need to regen before a boss fight. only use shrines when someone's dead and you dont think you can get them up in next combat. power regen should work by itself if you got a good tank and a good healer.
use revive potions when there are no shrines or stairs up. use healing pots if you think that someone may die before healer gets his turn. if tank or cleric is low on hp, give em a small potion. they together keep the rest of the team up.

if you are facing a difficult boss you cant beat, look through inventory after items that buff next combat. try to save 4 of each for the last combat though.

good luck.

lol STFU

yeah seriously shut the ( ... ) up and let people work it out. That's what the game is!

fun game! addictive
and only 1.17 MB!!!!!

hard, but fun

Sweet, thanks@asd