Okay I do fairly well until I get to Vierna's shade. I beat her with about 75% health left on my 3 pets. But once Vierna's shade comes around. I am lucky to get her down to 40-50% health before im out. I do take potions and go through wayyyy to many. Went through 20 health potions of 600, -Had used my others earlier to beat Vorpar- And over 10 revival draughts.

This is my team:
Chayson


He is a wind physical damage dealer, and his points are 10 in strength and 2 in Dexterity

Leeya


She is a wind tank, 10 points in health and 2 in strength

Nyun


He is a mage, 10 points in intelligence and 2 in agility.

Any advice would be amazing to improve my team, my equipment on them is currently the best I have.

Some threads you should read:

There's some stuff in here about the mechanics of the fight:
http://www.sylestia.com/forums/?thread=5984

This is the guide to speccing and gearing. I do see some gearing issues, and it sounds like your specs could stand to be redistributed for better effects as well:
http://www.sylestia.com/forums/?thread=11101

But basically the key to this fight is not having any mana when she does her Mana Transfusion. Keep your mana as low as possible until the First one, then on turn 1 heal, turn 2 fight, turn 3 heal, turn 4 finishing move and usually on turn 5 she'll try to do the mana transfusion - and if you do it right she'll get nothing.

Thanks a lot for that advice Divinis it helped a lot!