When close to a Fels, it is possible to briefly see their nametag "Dinnerbone".
Although it's an Enderman, it can be hit by arrows and fishing rods. Once they are hit however, they will teleport randomly then back to where it left off.
Unlike normal Enderman, Fels can swim in water.
The name Fels probably refers to Fel in game's lore, where it's described as a type of magic, connected to death, the dead and raising dead. It was used by Jythar, the Dragon Emperor when he was losing to make one final strike against humans, which lead to separation of the Skyblock Islands, the creation of Rift Dimension and the death of Kaeman's family. Jythar's heart was place on an island, which due to its aura staying strong after his death lead to creation of ⏣ The End island and its population. Additionally, using this power, Kaeman, became The Wither King.