Yuna

Yuna (ユーナ) is a Mother Unit who rules over the systems on Terra. She is accompanied by her Servitor Unit named Gatz.

Story
A long time before the events of Mega Man Legends 2, after the Master's death, Mega Man Trigger fought against the System to destroy it and fulfill the Master's dying wish, fighting against Yuna, Sera, and others. As time went by, Yuna slowly came to understand what Mega Man was trying to do, and decided to take a neutral position by neither helping nor fighting against him. Sera, frustrated with Yuna's decision, traveled to Terra herself to fight against Mega Man, and the two fought each other to a standstill as Sera wasn't able to bring her full power to bear outside of Elysium, both expending all of their energy and Mega Man's original body almost totally destroyed. After the battle, Yuna took that opportunity to seal both inside stasis fields, with Sera being imprisoned on Forbidden Island while Mega Man was "reseted" and was sealed with Data on Nino Island. As time passed, those events where remembered as an old legend about two goddess that watched the world, the sky goddess (Sera) who "guards the record of the ages" and the earth goddess (Yuna) who "guards the keys". When the sky goddess tried to borrow the keys from the earth goddess, they argued, and the sky goddess was imprisoned by the earth goddess on Forbidden Island.

Yuna watched over Forbidden Island since them, warning people to don't approach the island and saving Diggers that went there by putting them into hibernation. 30 years before the events of Mega Man Legends 2, she saved Barrell Caskett and Von Bluecher, and 20 years after this she found Matilda dying, and had to transfer some of her nanotechnology from her body to try heal her. Yuna used too much energy and parts of her body to save Matilda, to the point she wasn't able to move anymore, and had to "borrow" Matilda's body until her body was repaired, placing her original body inside of Matilda's dropship. Matilda's body is used by her since them.

In the beginning of Mega Man Legends 2, Yuna enters inside the Sulphur-Bottom disguised as a reporter to warn the people that the Mother Lode isn't a treasure, but a catastrophe waiting to happen, and escape from the guards with Gatz's help. Some time later, seeing they ignored her warning and where going to Forbidden Island, she asked Gatz to attack the Sulphur-Bottom as warning, but the attack damaged the engines and the Sulphur-Bottom was trapped in the storm until it fall. When Mega Man went to Forbidden Island to find the Sulphur-Bottom, Yuna's original body can be seen in Matilda's dropship, and is taken by her and Gatz after Sera's awakening, also awakening the Diggers she saved and taking them to the outskirts of Yosyonke City.

After the four keys where found by Mega Man and where stolen by Sera and Geetz, Yuna appears to help Mega Man and argue with them. After Geetz's defeat, Mega Man was damaged and Yuna repaired him with Data's help, learning why Mega Man wanted to destroy the System. She helps Mega Man to reach Elysium and stop Sera, guiding him throughout Elysium. After Sera's defeat, she convinces Sera to save her life by transferring her primary program to Yuna's original body. The game ends with Yuna, Sera and Mega Man in Elysium, without means to return to Terra.