The Masekii

>Begin Transmission: "Oh shit!, okay I don't think it saw me. No, no, no FUCK! It saw me, It saw me! Get!...Off!...Me!...Ahhhhh!" <End Transmission --UNSC serviceman's last known transmission

The Masekii (Latin, Monstrum intrepida, translated to "Fearless Monster" known by humans as Monsters, Reaper, & Shadow)