Sorry, Ironblood, but there are E and F characters.
E is Entrapta, a woman who could ensnare people with her Rapunzel-like hair. She was the only other toy-made HordesWOMAN apart of Catra.
F is False Face, a master of disguise who could change his appearance. He only appeared in the TV series.
However, Grizzlor is right for G.
Maybe it's my fault. Since I made the Evil Warriors and Horde to be listed apart, the Horde has much less characters than letters in the alphabeth. Let's make a deal: when we have finished the Horde, the "Heroic" listing A to Z will be general; Heroic Warriors, Great Rebellion, Galactic Guardians, etc. Deal?
Oh, and H is for Hordak.