Shiv costs a different amount of energy depending on the speed of your offhand weapon. Combat potions, such as primary stat potions and mana potions are still on a separate cooldown from health potions. Hunter � Hunters with a speed set can easily get over 200% movement speed, and are good for AoE farming. In general both should be carried, but as mages we're all lazy and generally don't even carry either of them. Speed, stealth, and invisibility potions from old expansions no longer work above level 50, you will have to use the new Shadowlands potions.
This makes leveling professions much easier since you don't have to grind reputations to get higher rank recipes.
