Single Target (Raid)
Key points about the single target build:
I don't recommend taking conjure mana gem because there is a lot of weird interaction with this talent currently, and it's not user-friendly + it's taking up a bag slot. Mana regen is not an issue for arcane mages once you reach enough mastery, so you have other better talents with this build.
The reason why I suggest picking time anomaly instead of temporal warp is that it helps with our mana regeneration early on when we can't get high enough mastery (you can pick temporal warp on fights; you use bloodlust on the pull to benefit from multiple bloodlusts)
Mythic+ & AoE
Key points about the AoE And Mythic+ build
The focus of this build is similar to the single target build we looked at, and the playstyles are also very similar.
Instead of Nether tempest, I recommend picking reverberate since it has more interaction with our barrage + mana regen and Arcane Barrage into Arcane orb into Arcane barrage combos with Arcane Bombartment.
This build's focus is to stack as many arcane harmony effect stacks as possible (at least 18 stacks) then you want a big orb barrage into orb combos with targets that are on execute range from Arcane Bombartment.
More on that in the rotation section.