Topic arcane,frost or fire
Poly morph one while killing the other, other one is frost nova then if you have scorch use it while moving further away, actually as a fire mage you have to have it,
What I do is pyro as an opener spam scorch until heating up, then use inferno/fire blast depending on your level, keep spamming scorch until pyro becomes instant cast then cast it and repeat from scorch.
Do not use fireball or frostfire, their casting time makes them laughable as a spell until higher level.
Quickest way of 2 mobs at the same time, think ive figured it out,
target one, pyro, then spam scorch while moving back, and inferno when heating up once the second is within range use frost nova, then walk back while casting scorch on the first, then once the first is dead if your low on health, ice barrier and then just repeat for the second.
if theres 3 then keep ice barrier for the third because it wont come off cd in time to use again.