#DnD Monster: The Pit Jelly
Hell prides itself on being prepared. It creates devils for all possible purposes. This one might be intended to assault acidic planes of the Abyss, or infiltrate areas too small for most fiends to enter, but still have the size and strength to truly fight. It resembles a greenish, translucent pit fiend, which indeed, it was created from. These creatures are most often found on Nessus or Malebolge.