Celtic Heroes

If you search you can find calibans ice Mage build which maxes ice shards. If you use lots of sigils it can be the most powerful build in the game. Even without sigils it provides lots of extra points to spend on support skills.

I defeated a freeze mage 30 lvls higher than me :p.

I only use firebolt, the only atk skill I have lol.

It is worth using ice shard since if you get to other world the mobs are fire based.Ice will therefore be weaker against fire based mobs. I hit 1728 with ice shard at 32/35 and lure dont need to be maxed 12/35 will reduce resistance of mob to zero. If you are killing lavalord fire wont work on him as fire heals him so u will definitely need ice shard