Arcane Explosion is honestly terrible compared to R9/R8/Blizz. If you do two flamestrikes then blizzard clearcasting will often proc for blizzard, which means you have increased crit for the whole blizzard duration. (Even then, blizzard would do more even if it didn't crit)Originally Posted by Pasture
The only time you should do explosion is if mobs will die very fast or when it's not possible to channel.