For the Rift Guardian, see Raiziel.
Razael the Feared, Shadow's Bane, is a unique Winged Assassin that can be found in Pandemonium Fortress level 1 in Diablo III.
It has Electrified, Nightmarish and Reflects Damage affixes.
Razael is required for the Special Assignment achievement; however as it is not named as a bounty it may prove to be highly elusive for the purpose of that achievement.