Presence of Mind

Presence of Mind is a mage ability that when activated, causes the next spell with a casting time less than 10 sec to be instant. For example, activating Presence of Mind and then casting Pyroblast will instantly hurl a fiery ball without that spell's normal 6 second casting time. Presence of Mind only affects spells with a cast time less than 10 seconds, which only excludes Teleport and Portal spells.

Tips and tactics
Presence of Mind is used mainly to achieve burst damage. It is often used in conjunction with Arcane Blast or Frostfire Bolt (no longer Pyroblast cause it's impossible to have both spells at the same time) to deal a large amount of damage without the normal cast time.

Once Presence of Mind is activated, the next instant spell can be cast while on the move, where it would normally require the mage to stop and cast. Thus, it can be used to cast large nukes while jumping or falling.

This ability is also useful with Polymorph. Sometimes a mob is beating on you and casting Polymorph will take longer due to damage interrupts, or the mob is a hard-hitting elite and will one-shot you, and an instant Polymorph is needed to survive.

Taking Arcane Potency along with this talent greatly increases its burst potential by increasing the instant spell's chance to critically strike (provided it can do so).

This ability is popular with the so-called Three-Minute Mage, a play style that gets its name from this ability and Arcane Power, which both originally had a 3-minute cooldown.