On the mage discord, I would like to shout-out WoTLK Gold to him for the great work on this and the great review in the pin and I also have it as a NightBot command on my channel in discord and crediting it to him. He has shown that you can hard cast Arcane Missiles with more mana effectiveness and less damage over Arcane Barrage.

In other words, even if you do not have a procand you're at 60x and don't have a missile barrage proc, you'd have to cast your WOW WoTLK Classic Gold Arcane Missiles and this has been called missile barrage, gambling.

And the reason for that is because after you have completed that last Arcane Blast, like right here, if I just make an Arcane Missiles right into it, there's still a 40 percent chance that the Arcane Blast finishing the cast will result in an missile barrage Croc.