Ophiuca

Ophiuca, known as Ophiuchus (オヒュカス) in Japan, is a manipulative FM-ian based on the serpent-tamer constellation, Ophiuchus. Her form is that of a dark purple Nāga, with the power to control snakes.

Personality
Ophiucus in the game speaks in a formal way, and was quite manipulative, coercing Luna to merge with her and punish her parents for how they treated her. She seems to have a fondness for Omega-Xis, as she asked him to join her and to give her the Andromeda Key, and stating that she would get Cepheus to give the controller, and she and Omega-Xis could rule FM together. However, when she was turned down, she immediately turns vicious and attacks, even asking Gemini to help her defeat Mega Man after being defeated by Mega Man. She also seems to be disappointed at how Omega-Xis had lost his 'fangs' by becoming too kind and taking hits for Lyra Note when they were forced to battle them.

In the anime, Ophiucus retains most of her personality from the game, being rather formal and manipulative, but has more loyalty to her planet and King, unlike the game, where she plotted to overthrow Cepheus with Omega-Xis. She is rather cunning at times, as she knew well on how to use Taurus' habit of getting excited from seeing the color red to her advantage, and even making some strategies on gathering negative energy from the humans.

However, later on in the anime, after being stranded on Earth with her fellow FM-ians, she began to take on jobs as W Luna, trying to earn money to feed her comrades, which caused her to have a more humorous personality, as she began to value the hardships of earning money, even going as far as going grocery shopping on a bargain sales day, rushing at wherever there was a sale.

This also causes her to grow angry when her comrades end up carelessly spending money or asking for more expensive food and such. She was absolutely horrified and heartbroken when Cancer once spent all her savings to buy a device, even making her start crying at the end.

From all that, Ophiucus had also developed a love for shipping as after being sent a message from Cepheus to return to the world, and the FM-ians decided to spend some days preparing to leave, to which Ophiucus stated that she would spend her time shopping, using all her savings since she would no longer need them after returning to her planet.

Mega Man Star Force
In the game, because of Luna's involvements with numerous FM-ian incidents, caused her parents to transfer her to a new school. She keeps this painful news away from her friends. At the mall, she observes Geo and Sonia while they attend a jungle exhibit, and tailed them out of jealousy. There she has an unexpected run-in with her parents, and the confrontation prompts Ophiuca to appear before her. Ophiuca promises to make Luna's parents pay, and Luna allows Ophiuca to invade her heart, merging them together to create Queen Ophiuca. Queen Ophiuca holds Luna's parents hostage demanding Omega-Xis to hand over the Andromeda Key so that they may "use its power together". Mega Man eventually defeats Queen Ophiuca, but she was not finished off since Omega-Xis doesn't go hard on women (like Lyra, whom he also did not finish off.). Gemini appears by voice, while Ophiuca asks him to defeat Omega-Xis, who says the two of them together will be a tough job. However, Gemini kills Ophiuca on a whim.

After being defeated, Cepheus later resurrects Ophiuca and sends her after Mega Man to stop him from approaching Andromeda, but she lost.

Mega Man Star Force 2
Ophiuca does not appear in this game. However, after Hyde kidnaps Luna, he forces the remains of Ophiuca's data to transform Luna into Queen Ophiuca.

Mega Man Star Force 3
Ophiuca does not appear in this game as a boss, but instead, as a Noise Change.

Anime History
In the anime, Luna suspects that Mega Man is unaware of his secret identity. It was because of this weakness that she is targeted by Ophiuca during one of Sonia's concerts, taking advantage of Luna's desire to see her hero and her jealousy over Harp Note, who she believes may be romantically involved with Mega Man. Luna allows Ophiuca to invade her heart, merging to create Queen Ophiuca. Mega Man and Harp Note team up and defeat her. Unfortunately, Ophiuca escapes.

Later, Ophiuca takes on the form of W Luna while gathering minus energy to recreate the Andromeda Key. During this time, Ophiuca often bickered with other FM-ians over how to spend money, and she herself also developed a love of shopping. Eventually, Ophiuca is deleted by Gemini Spark in order to fill the Andromeda Key.

Etymology
Ophiuchus is one of the 13 constellations that crosses the ecliptic. In astrology, Ophiuchus is considered the 13th sign of the zodiac.

Trivia

 * A noticeable feature between the game and the anime is a minor part in Ophiuca's appearance. In the game, she is displayed holding a flute with both hands (giving the image of a snake enchanter); however, in the anime, the flute is absent. It is unknown if this was a mistake or not.