Orion Fowl is Artemis's alter ego, created as a result of Artemis succumbing to Atlantis Complex. He makes his appearance in the 7th book, The Atlantis Complex, when Holly zapped Artemis with her Neutrino, and when shocked by Amorphrobots . Orion has a guilt-free, unrealistic, confident personality, with all of Artemis's memories and knowledge but none of his guilt. Orion is also free from the other symptoms of Atlantis Complex, including Artemis's irrational fear of four (which sounds like the Chinese word for 'death') and his belief of five as a lucky number.
Orion appears incapable to distinguish the difference of magical creatures of the real world and magical creatures in fantasy novels. Holly Short also stated that he had 'spent too much time in the back of Artemis's head'- he doesn't know how to interact with the real world. Orion has an obvious affection for Holly and expresses this in romantic lines and by calling her his "princess", much to her annoyance. He is extremely gullible to fantasy, as he suggests that Foaly and himself look for magic rocks and a secret birthmark to prove he is a prince. Orion speaks as though as he is a fantasy hero, calling Foaly a "noble steed".
However, Orion proved to be vital in the eventual success of Artemis's scheme, as when he was branded a rune and enthralled by Turnball Root, Artemis tried to get himself shocked to let Orion become the dominant personality. Orion had fighting skills he had learned from Butler which Artemis usually ignored, and defeated a similarly enslaved Holly and Turnball.
"I suggest a bivouac, and perhaps we could gather kindling for a campfire, and some leaves to make a cushion for the lovely lady."
- pg. 107
"I'm just a teenager with hormones running wild. And may I say, young fairy lady, they're running wild in your direction."
- pg. 137
"Oh, I'm crazy all right. I do have plenty of psychoses. Multiple personality, delusional dementia, OCD. I've got them all, but most of all, I'm crazy about you."
- pg. 137 "I don't have much experience with real people, or feelings that translate to the world. But I think I am sad now. And lonely. WE have lost a friends."
"Good. Then, worthy centaur, perhaps you could give me a ride to the village on your back. Then I can make a few pennies with my verses while you build us a shack and perform circus tricks for passersby."
- pg. 150
"How do I love thee? Let me see. I love thee passionately and eternally... obviously eternally - that goes without saying."
- pg. 181
"Ladies don't look for birthmarks; that is work for jolly fellows, like the goodly beast and myself. Ladies, like Miss Short, do enough simply by existing. They exude beauty, and that is enough."
"I am not exuding anything." (Holly)
- pg. 181
"You have displeased the princess!"
- pg. 182
"I feel a little dizzy, but also wonderfully elated. I feel that I am on the verge of finding a rhyme for the word orange."
- pg. 189
"But [Artemis's] sonnets are heartless, and that opera house he designed was totally self-indulgent."
- pg. 190-1
"Very well. Then quiet it shall be. I would rather cut out my own tongue than utter one more word. I would sooner behead myself with a butter knife than speak a single -"
(At this point Holly jabs Orion in the solar plexus)
- pg. 191
"For I am not Artemis Fowl, villainous elf. I am the young romantic who always knew his day would come, so I listened to Butler and I am ready."
- pg. 342
"Be still, foul demon'!"
"Apologies, gentle mage. I was referring to my piratical foe."
- pg. 343
"That woman is quite a pilot. I imagine they are holding hands now and smiling bravely."
- pg. 346