ok this will only work on some comps since u need common mechanics
What u want to do is;
1. Ice lance the warrior 5 times
2. Root him with frost nova.
3. Run away slowly with hamsting.
4. Cast frostbolt BUT DONT LET IT FINISH! Cancel it like 2/3rds of the way of the cast time.
5. Warrior hopefully spell reflects, ice lance him, it gets reflect so u get ice lance.
6. have ur priest dispell ur winter's chill = u get the 10% crit buff from talents. I just discovered this and wrote it :> Hope it can help u as much as it helped me!
10% crit + frostbolt spam = winwinwwinwiwnwin


even sicker if u have BL ^^