Shadowfright is an inhabitant of the Moon twisted by the Nightmare Energy. Normally a draconic creature with avian features, his corrupted form is a mass of spectral purple smoke, though his face is still distinctly bird-like. He is darker and larger than the majority of other Nightmare Creatures. His eyes are red and highlighted with black.
Shadowfright is very full of himself and prides himself on being terrifying, reacting with anger whenever anyone calls him by his host's name, Larry (except for Nightmare Rarity, his mistress). He is always serious and despises goofiness and incompetence, which makes him scorn Jerome. As the secondary leader of the Nightmare Forces, he is highly manipulative, exploiting Rarity's flaws and weaknesses to leave her open for the Nightmare's possession.
When freed of the Nightmare's influence, Larry is actually a very pleasant being to be around, making up with Jerome.
Shadowfright leads the Nightmare Forces. Their origin is not revealed, but they joined with or possibly even created Nightmare Moon (possibly the outside force who magnified Luna's jealousy and bitterness to transform her, although the TV series may yet reveal a different villain to be this force). They told her what to do to get ponies to fear her, and she promised them a kingdom of their own. When the Mane 6 used the Elements of Harmony to restore Luna and destroy the evil in her, Luna thought the Nightmare Forces would wither and die without her. Instead they went to the moon where they would be granted one more chance through the cycle of the new moon.
Role in the comicsIn Issue 5, the Nightmare Forces gave the Mane 6 nightmares, and captured Rarity, taking her to the nightmare dreamscape on the moon. In Issue 6, Shadowfright was successful in turning Rarity into their new queen, Nightmare Rarity (hinted at being possessed by the spirit of the original Nightmare Moon). He and his minions gave the other ponies nightmares as they traveled to the moon to rescue Rarity, but were pulled out of the nightmares by Spike and Luna. Shadowfright, hinting at a secret Luna kept from everypony, tried to convince her to become Nightmare Moon again. She declined, and Shadowfright revealed Nightmare Rarity.
In Issue 7, Shadowfright was defeated by Rainbow Dash when she caused him to crash, but he recovered and nearly captured Luna, but Twilight zapped him with a magic spell allowing Luna to escape before Shadowfright captured Rainbow Dash, while his minions captured the others. When his sidekick lost the key to the dungeon, Shadowfright sent him to find it. Later, both trapped Spike with their tails when he entered the Nightmare Forces' castle.
In Issue 8, Shadowfright destroys Spike's Fire Ruby before he and his army attack Ponyville, but with the help of Twilight and the others, Luna destroyed the Nightmare Forces and decorrupted the moon creatures they were possessing. Shadowfright was a corrupted or possessed birdlike creature who, once restored to his true form, prefers to be called Larry.
Shadowfright is made of pure darkness, which allows him to reshape his body into whatever he needs for attacking, including tentacles and hammers. Like most Nightmare Forces, he is able to fly.
He may also possess the ability to induce nightmares in others.