Epsilon

Epsilon is the "Unknown Energy Manipulator: Test Model" from Mega Man X: Command Mission. He serves as the leader of the Rebellion Army and acts as the game's antagonist up until the final chapter.

History
Epsilon masterminded the revolt on Gigantis Island and is the leader of the Rebellion Forces. Proud and relaxed, he is usually very quiet. Epsilon was the only Reploid to survive the Supra Force Metal infusion experiments, giving him heightened intelligence and strength capabilities. All other volunteers in the experiment either went mad (maverick) or perished outright. Though Epsilon retained his sanity, he realized he could try to reproduce the same results that he had on other Reploids, and thus staged a revolt for Reploid Freedom, believing that Reploids could evolve past what humans had made them to be, and become more advanced. He led the Rebellion with great charisma and leadership, so much that Scarface and Ferham were willing to put their lives at stake for him. His body also contains a sizable chunk of Supra Force Metal, still.

Throughout the game, Epsilon makes attempts to control Giga City's resources while crushing the Resistance that opposes him. Realizing he needs force to make others listen to his ideals, he resorts to creating a missile armed with Supra Force Metal to keep his foes at bay. Eventually, X and his team make their way into his fortress to confront him. After Scarface falls in his name, Epsilon takes them on himself only to lose. As he tries to continue fighting, X brings him down with his buster.

After the end of the game, Epsilon was deferred of all Maverick charges posthumously, most likely due to the restraint he showed in not killing any innocents during his activities (having banished the humans from Giga City with no harm, simply forbidding them to return) and the fact that his whole Maverick status came about as a result of Redips' manipulation of events.

Abilities
As a result of Supra Force Metal testing, Epsilon is extraordinarily strong and durable, as it took six Reploids to take him down. Using his implanted Supra Force Metal grants him even more devastating attacks, as well as alternating resistance to Combat and Shot attacks and regeneration capabilities until his Supra Force Metal output has been weakened by damage.

Epsilon is also shown to be quite intelligent, able to conceive the idea of Reploid evolution and plan out the goal of controlling Giga City to reach those means. His ability to lead and charm others inspires great loyalty in those who serve him and helped in convincing Shadow to join him early on (though what ultimately accomplished the latter was the Supra-Force Metal). Another sign of his intelligence is in the hierachy of his Rebellion Cadre, as it indicates a level of dignity, true conviction, and trust: the order generally dictates that the more loyal, restrained, honorable, and/or righteous a reploid is as opposed to being mad, power-hungry, and in essence truly Maverick, the closer to Epsilon in the Cadre ranks he or she is likely to be. The only high-place Cadre who seemingly defies this is Botos, but his selfish qualities are mostly kept discreet and even he seemingly falls right below Scarface and Ferham in command.

Trivia

 * Epsilon is the fifth letter in the Greek alphabet. (Sigma is the eighteenth.)
 * Also, Epsilon and Sigma share an English voice actor in Dave Pettitt.