Warlock · Demonology · tier 3 · from level 20
Master Summoner
Master Summoner
Rank 2/2
Reduces the casting time of your Imp, Voidwalker, Succubus, Incubus, and Felhunter Summoning spells by 4 sec and the Mana cost by 40%.
Doesn't change the damage or healing of any Warlock spell.
Averages, counting crits and misses, for a level 60 Warlock with a typical weapon and no other gear or buffs, against a target your level. Worked out from the game's own data, the same way as the Foresight addon.