Harpies are a female humanoid-bird creature. They have venom in their claws that can kill you easily. They are responsible for Liza Koshy's death.
Episode 5 - The Gingerbread Woman
After Tyler and Liza escaped from the Gingerbread Woman and trapped her in her oven killing her. They give the gem to the others when The Sorceress comes out and states that they forgot something the most important rule of the games one of them must die. Then an orange Harpie comes out holding Sampson. The Sorceress then orders for her to kill him she does via snapping his neck and throwing him inside. Then a door opens and another Harpie comes out grabbing Liza and drags her inside pulls her inside and then kills her then blood splatters against the window. symbolising Liza's death.