Dark Pact

Dark Pact is a common warlock spell card, from the Kobolds and Catacombs set.

Strategy
This card offers a substantial amount of healing for Warlocks, at the cost of a friendly minion. While a weak 1/1 can be sacrificed for healing, it's better to use this card as a Deathrattle activator, namely ones that can bring out a big minion like Devilsaur Egg, Possessed Lackey, and Carnivorous Cube.

A more advanced usage for Dark Pact is to guarantee your minion dies. This is not only important for activating Deathrattles without risking being silenced, but also for resurrection effects like N'Zoth and Bloodreaver Gul'dan; if the minion is transformed or stolen with cards like Polymorph and Mind Control, you will not be able to take advantage of those effects because they will not be added to your pool of destroyed minions.

Lore
, originally named Sacrificial Pact, is a level 75 warlock talent which sacrifices 20% of the warlock's demon minion's current health to shield the caster for 400% of the sacrificed health for up to 20 seconds. If the warlock has no active demon, a portion of their own health is sacrificed instead.

Trivia

 * Dark Pact originally cost '0' mana during the development of Kobolds and Catacombs.

Patch changes

 * Now restores 4 Health, down from 8.
 * Added.