Le Mu

Le Mu (ラ・ムー) is the final boss in Mega Man Star Force 2. In the legends of Mu, he is said to be the god of EM Waves, in addition to being the ruler of the continent of Mu. After the Mu people's destruction, Le Mu fell into a deep slumber, until reawakened by Lady Vega with the power of the OOPArt(s).

In the Alternate Future, Le Mu had given life to a successor EM Being, known as Apollo Flame.

Mega Man Star Force 2
Le Mu first appears in the throne room of the Great Shrine area on the floating continent of Mu. Lady Vega reveals to Hyde that Le Mu is the "god of EM waves". Once awakened, Le Mu begins creating copies of the Mu UMAs and Murians and sends the UMAs towards Earth, invading the entire world. Mega Man proceeds towards Mu, and is warned by a Hertz that the legends say the god of EM waves resides there, but Mega dismisses it as a legend.

Later, Mega Man reaches the Great Shrine, and Vega calls him into the throne room. She tells him of Le Mu, and that he is a god, but Geo and Omega-Xis don't believe her. She also tells them of her past, and of her plan to become a god to rule over the people of Earth in order to fix society by dividing it between the talented and the foolish. She says Le Mu is responsible for making Mu an advanced civilization, lifting the continent, creating endless supplies of Mu EM bodies out of nothing, and creating the EM Wave World itself. Mega Man refuses an offer to join Vega, and engages in a final confrontation with Le Mu. Mega Man wins, but in a last and suicidal attempt, Vega orders a heavily-damaged Le Mu to smash Mu into the ground to blow the Earth up.

Mega Man tries to stop her, but Hollow ends his battle with Rogue and appears to assist her. Mega Man damages Hollow, and discovers he is a Matter Wave shaped like a human. Vega tells Mega Man of her dead lover, Altair, and of Hollow's past. Le Mu then becomes out of Vega's control and starts exploding from all of his injuries, and a powerful explosion throws everyone a small distance from the Shrine Room. Hollow shields Vega with his body, and is killed in the process. His last prayer travels beyond dimensions, and a miracle temporarily brings back Altair's voice to speak with Vega.

Just as Mega Man speaks with Vega, Le Mu reawakens, and continues to carry out Vega's last order. Vega leaves, and Mega Man heads back to finish what has been started. He shoots twice, but Le Mu is unaffected. Mega Man falls, but his friends call his Star Carrier and tell him that the whole world is listening to his bravery. Encouraged, Mega Man stands up and destroys Le Mu with one final shot from his Mega Buster, causing the entire continent of Mu to collapse into the ocean.

During the extra storyline involving the Alternate Future and Apollo Flame, Mega Man gathers the five seals of which Apollo spoke, and returns to face a more powerful Le Mu, known as Le Mu Xa. There is no story explanation to this, being only an extra game challenge.

Once Mega Man defeats Le Mu Xa, a different ending occurs. Rogue rescues Mega Man from the collapsing continent of Mu, but brings him to the deepest part of the Whazzap Ruins. There, he challenges Mega Man as Rogue SX to a final showdown between his acceptance of loneliness and Mega Man's Link Power.

Shooting Star Rockman Tribe
Le Mu has only a brief appearance, and is seen attempting to crawl through the portal connecting Mu and Earth near the end of the series. Rogue appears at the portal's exit to hold Le Mu back. He commands MegaMan, in Tribe King form, to use the power of the OOPArts to seal the portal to prevent Le Mu from destroying Earth. Mega Man does so using Czar Delta Breaker, destroying the portal and sealing Le Mu and Rogue with the continent for good.

Abilities

 * Shell Protection: In order to damage Le Mu, the player must first deal enough damage to his outer shell. The shell's color is an indicator of how much damage it has taken. After it is destroyed, Le Mu will become mobile, moving from side to side, and the only way to hurt it is to hit its core when it is lit.
 * Super Armour: Le Mu cannot flinch.
 * Status Guard: Le Mu is immune to status ailments except for counter-induced paralysis and HP bugs.
 * Materialize Drill: Le Mu summons a drill and fires it at the player, 2 before the shell is broken, 4 after. This attack cannot be blocked.
 * Materialize Big Vulcan: Le Mu's arms transform into vulcan guns and fire multiple times at the player's position.
 * Materialize Blade: Le Mu's arms turn into blades. They then smash two adjacent columns each side of the field. This attack cannot be blocked.
 * Materialize Murian: Le Mu will summon a Murian that will attack the player's current position, either with a sword or a laser. This attack's element depends on the color of the summoned Murian: Red - Fire, Blue - Aqua, Yellow - Elec, Green - Wood, Purple - Null.
 * EM Vortex: Le Mu occasionally summons a vortex on the player's row. If the player stands on it, his HP will be drained while he stands on it.
 * Mu no Ikazuchi/Thunder of Mu: Le Mu charges up some energy and fires a laser that covers the entire battlefield. This attack cannot be dodged, and blocking it will only reduce the damage done partially, unless it is blocked at the right time.

Battle Card
As the final boss, Le Mu doesn't drop Battle Cards, but a Giga Card of him could be obtained for a limited time in events.

Trivia

 * Le Mu's Japanese name "Ra Mu" sounds similar to Ra Moon from Super Adventure Rockman, from the classic Mega Man series. They are both found in the ruins of an ancient society and use some form of electromagnetism (Ra Moon using EMP waves, whereas Ra Mu makes endless "EM bodies").
 * He is the only final boss in the Star Force series which has only 2000 HP in his first fight, unlike Andromeda and the Crimson Dragon who have 2500 HP each.