Iris

Iris, (Ἶρις in Ancient Greek) is the Goddess of the Rainbow. She delivers Iris Messages for gods, goddesses, and if asked nicely and she's not too busy, for demigods. Interestingly, her affiliation is unknown, as she has been known to deliver messages for both gods, demigods, and Titans. It is possible that she was neutral in the Second Titan War because she was too busy carrying messages, as she wasn't among the many minor gods and goddesses who had switched over to Kronos' side.

History
Iris is the daughter of Thaumas, one of the many minor sea gods, and the ocean nymph Electra, an Oceanid. Her sisters are the Harpies, Aello, and Ocypete. She also has a twin sister, Arke, who served as messenger for the Titans in the first war and was thrown into Tartarus with her masters by Zeus (after ripping her wings off). As the sun unites Earth and heaven, Iris links the gods to humanity. She travels with the speed of wind from one end of the world to the other, and into the depths of the sea and underworld. She is married to Zephyrus, who is the god of the west wind. Their son is Pothos. She also wields a pitcher of water originating from the River Styx. Whoever promises to tell the truth and lies, she uses it to put the liar to sleep. She was said to bear golden wings of a butterfly and she is commonly underestimated as goddess of rainbows, but her children are, in the case of Butch, rather powerful.

Percy Jackson and the Olympians
Throughout the series, Iris' services are called upon (by throwing a drachma into a mist) so that the characters may communicate with each other.

The Sea of Monsters
Iris is mentioned to be on good terms with Hermes, as they are both messenger gods, and always helps the demigods in moments of peril. Chiron mentions that he and Iris have been friends for centuries and that he asked her to notify him if anything strange happens in the Miami area.

The Last Olympian
A cabin is built for her demigod offspring after The Last Olympian at Camp Half-Blood.

The Lost Hero
Iris is the mother of Butch in the series. Even though Zeus forbade the gods to interact with the surface, Iris still sends Iris Messages for the demigods; making an exception for her as a messenger. The demigods also use her to contact their allies.

The Son of Neptune
Iris is first shown when a giant rainbow appears before the army of monsters approaching San Francisco. They attack the light, but it burns their bodies and melts the weapons into rainbow colors. She then throws a gluten-free, no-sugar-added, vitamin-enriched, soy-free, goat-milk-and-seaweed-based cupcake simulation (which the monsters assume is a grenade and which both parties assume is a Ding Dong) at the horde when they demand food. She says that she has eased up on her duties as messenger of the gods and has opened a chain of stores called Rainbow Organic Foods & Lifestyles (R.O.F.L). The stores are described as having "bins of nuts and dried fruit, baskets of apples, and clothing racks with tie-dyed shirts and gauzy Tinker-Bell-type dresses." The entire store is adorned with wind chimes, crystals, geodes, dream catchers, macrame, and other "strange stuff." Iris tells her employee Fleecy (who she now has handle Iris-Messaging) to give an ailing Percy "green tea with organic honey and wheat germ" while she talks with the others.

She encourages Frank to reject the quest and his destiny, live without the gods, while showing him visions of his past to try to explain his gift. She also offers to hire him, but he declines. She prompts him to seek Phineas and ask him for help, but not to kill her sisters, the harpies. She also instructs him to use his spear to kill the basilisks. Her last words of advice come with a prophecy - he will die holding his piece of tinder, but he will live longer if he gives it to someone he cares for. She gives Percy Jackson a tie-dyed "masculine accessory bag" (a purse) that she states looks "good" on him before they leave to continue their quest.

Personality
Iris is a free spirit. She is mostly a non-violent god that only attacks in self defense. She is also upset that living a life for others (by delivering messages for others) has left her with no identity, as there are no shrines to her or a sacred animal. Because of this, she opened up her own store and is doing what she wants to do, advise she passes on to Frank.

Appearance
Iris has olive-coloured skin, long black hair and warm brown eyes. She appeared as a middle aged woman to Frank, Hazel and Percy. She reminds Frank of his mother by the way she smiles, with one side of her mouth, her warm brown eyes and the way she tilts her head like she's considering a question.

Abilities
Most of her powers are unknown but the following is known because her son Butch has demonstrated a few powers:
 * Iris' powers are summoning pegasi, rainbows, and blasts of multicolored energy.
 * She can also move at extremely fast speeds (so she can deliver messages)
 * She can use rainbows to reflect off objects so she can project them off as rainbow– colored beams that can cause great damage in buildings.
 * She can possibly manipulate light, as Apollo and his children can.
 * She can use light from her rainbows to create multicolored flames and burns to ward away enemies.

Iris-Messaging
Iris is also able to create Iris messages. To Iris Message someone, you must find or make a rainbow (easier in modern times with the advent of the water hose with which you can get a fine spray) and throw a drachma through it, then say:

"O, Iris, Goddess of the Rainbow, accept my offering."

and name who you wish to speak to and where they may be found. It has changed in The Son of Neptune.

She is also friends with Chiron, (and has been for centuries), allowing him to eavesdrop on some Iris-Messaging as shown in The Sea of Monsters.

Roman demigods do not use Iris-Messaging, as by the time that Rome conquered Greece, they used more advanced methods such as "giant eagles" or their road system.

Trivia

 * 7 Iris, a large main belt asteroid, is named after her. It is one of the brightest objects in the asteroid belt.
 * Iris is a species of flowering plants with rainbow colored flowers, named after her.
 * Iris, the colored part of the eye, is named after her.
 * Iris and another goddess have similar names; Isis who is also a goddess of rainbows in Egyptian mythology.
 * When Iris asked Frank to stay with her it was like how Calypso asked Percy to stay at Ogygia.
 * She is said by Frank to look at lot like his mom, sharing the same eyes color, hair color, and cocking of head when considering a question.