Blood Tap – Each damaging Death Coil, Frost Strike, or Rune Strike generates 2 Blood Charges, up to a maximum of 12 charges. Blood Tap consumes 5 Blood Charges to activate a random fully-depleted rune as a Death Rune.
*A guaranteed Death Rune from fully depleted runes when you want it as long as you have at least 5 Blood Charges.
Runic Empowerment – When you land a damaging Death Coil, Frost Strike, or Rune Strike, you have a 45% chance to activate a random fully depleted rune.
*Able to game runes with this to get back certain runes. Keep in mind you must have a fully depleted rune for this to do anything. This is currently the top simming option from this tier and is the best option for frost on multiple targets.
Runic Corruption – When you land a damaging Death Coil, Frost Strike, or Rune Strike, you have a 45% chance to activate Runic Corruptions, increasing your rune regeneration rate by 100% for 3 sec.
*Returns 30% of 3 runes. This will not actually last for 3 seconds unless you have 0 haste but will last for shorter amounts of time as your haste goes up so that you are always getting 30% of each rune regardless of your haste.
But since you want it for a PvP application you might want a more on use ability like BT. Preference really...just like Blizz wanted it to be.