- You can't make me bleed if my blood isn't pumping, can you?
Icy Veins is a talent trained mage spell that increases the casting speed of all spells by 20% and increases the chance to avoid interruption caused by damage while casting any spell by 100% while active.
Icy Veins does not reduce casting time of mage spells by 20%, instead it actually grants the mage a 20% spell haste, which means casting time is reduced by (100%-100%/120%)=16.67%. As of 2.4, the tooltip states the correct effect - previously it stated a flat 20% increase.
Under the effects of Icy Veins, spells that normally take 3 seconds to cast will then take 2.5 seconds. Spells that were 2.5 seconds will then cast in 2.08 seconds. Spells that cast in 1.5 seconds will then cast in 1.25 seconds.
Like all haste effects, Icy Veins will speed up all channeled spells, such as Blizzard, Arcane Missiles, and even Evocation. Note that spells will cast at the faster cast time even if the Icy Veins buff expires while mid-cast or mid-channel, meaning that the buff is effectively longer than the 20 second buff duration. For example, starting to cast a Pyroblast with Icy Veins about to expire in half a second will still cast a Pyroblast that finishes in 5 seconds.
Like most temporary self buffs, Icy Veins can be used off the global cooldown, and does not trigger it.
This talent was introduced in Patch 2.3.2, as a replacement for Ice Block but in Cold Snap's place in the talent tree.
Patch 2.4 changed this talent from increasing the chill effect ability to freeze the target by +10% to the avoid interruption effect.