Nephilim
Native to Ravnica. The Nephilim are massive monstrosities with limited intelligence that hold positions of fear and awe in Ravnican mythology. They were subdued thousands of years before the events of the Ravnica: City of Guilds block of sets and imprisoned deep below the plane's surface. Their precise origins are unknown. Once awakened by construction works in the Utvara district, five of the creatures fed on a dragon corpse and grew in size and power, showing a shared ability to absorb power from other beings. Two were defeated by the dragon Niv-Mizzet; the remaining three made it to the center of Ravnica City where they were eventually subdued.
The name "Nephilim" is taken from the biblical creature of the same name. In the game, the Nephilim were the first cards printed that needed exactly four different colors to play. None saw any tournament play, however, as their admittedly unique abilities were not seen to justify the difficulty of assembling those colors.
(Dune-Brood Nephilim, Glint-Eye Nephilim, Ink-Treader Nephilim, Witch-Maw Nephilim, and Yore-Tiller Nephilim)
Read more about this topic: List Of Species In Magic: The Gathering