Increases your spell damage by X%, and your pet's criticals apply the Demonic Pact effect to your party or raid members. Demonic Pact increases their spell power by Y% of your spell power for 45 sec. This effect has a 20 sec cooldown. Does not work on Enslaved demons.
Increases your spell damage by X%, and your pet's criticals apply the Demonic Pact effect to your party or raid members. Demonic Pact increases their spell power by Y% of your spell power for 45 sec. This effect has a 20 sec cooldown. Does not work on Enslaved demons.
Demonic Pact is a passive warlock talent that increases the Warlock's spell damage, and Spell Power of all party or raid members when the Warlock's pet scores a critical.
Demonic Pact is very beneficial to have in 5-man instances, and even better in raids.
For example, if you have +2000 spell damage, then this will add +200 spell damage to all raid members much of the time.
The Demonic Pact buff does not stack, but the 45 second countdown is reset if the pet scores another critical before the effect expires.
Patch 3.3.3 (2010-03-23): This effect now has a 45-second duration, up from 12 seconds, and a 20-second internal cooldown.
Patch 3.3.2 (2010-01-02): The damage bonus granted the warlock by this talent has been increased from 1/2/3/4/5% to 2/4/6/8/10%. The buff granted to a raid or party by this talent remains unchanged.
Patch 3.3.0 (2009-12-08): This talent now also increases the warlock's spell damage by 1/2/3/4/5%.
Edit
Patch 3.3.3 (2010-03-23): This effect now has a 45-second duration, up from 12 seconds, and a 20-second internal cooldown. 
