what ive found is: try to find the max distance for your ice(root) cast that first follow with fireball and flame wind line then immediatly recast ice then sprint back to max range and start over. with the short down time in mana refill its pretty good soloing xp.
This spell is a very short Root that stops movement for a few moments, afterwards the mob moves at an extremly slow pace for a few seconds. However if you do any damage to the mob this effect wears off. Be warned. =)