I heard that Wintertusk gave lots of xp and would make Celestia much easier. However, even the first few Skeletons are extremely difficult for me due to their tower shield spam and high damage output. I cannot kill them fast as I am an ice, and cannot Balefrost to reliably kill. Wintertusk is a struggle already and I have just started it!
Going through Wintertusk on my first (balance ) wizard was what prompted me to make an ice wizard! Ice is hard to beat with the tower shields and high health. Being an ice wizard was terrific and I loved not worrying about dying in WC, KT and MB. My ice wizard is now level 85 in Azteca so she finished WT long ago, but she won a fire mastery amulet in Water Works and built a fire gear set with some dropped and some crown gear to fight ice enemies in WT and ice bosses in the higher worlds. Though she could have probably done well using ice shields and prisms, being able to switch from ice to fire quickly (thanks gear set option!) works for her and makes her very strong! Plus a fire wizard is the one school I do not have, so it is neat to use the treasure cards and basic fire spells she has trained - enchanting them. So I wanted to put that out there as a suggestion to you since you are an ice wizard. Try fire as your secondary school and see what happens! Fire mastery amulet helps but is not necessary to build critical hit gear.
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