Iris

"Let's live together, in a world where only Reploids exist..."

- Iris on her deathbed, her idealistic world to live in

Iris (アイリス) was Zero's Navigator in Mega Man X4 and X's in Mega Man Xtreme 2. She was also the younger twin sister of Colonel. Like her brother, she speaks with a British accent in the English language versions of Mega Man X4.

History
She was developed by Repliforce scientists as half of the perfect fighting Reploid. Colonel, her brother, was the other half. Her half was of the peaceful arbitrator, and Colonel's was of the strong-willed fighter. Repliforce scientists had struggled to make these two factors into one Reploid, but the differences were irreconcilable, so they split them into brother and sister Reploids.

Mega Man Xtreme 2
The Erasure incident in Mega Man Xtreme 2 was Iris' first mission as a Navigator for the Maverick Hunters. She took the roles of both Navigator and item development by making power-ups out of the Maverick's DNA Souls. In the Xtreme Mode ending, Zero feels bad that her first mission was a tough one and the Colonel will blame him.

Mega Man X4
When the Repliforce was labeled Maverick after the Sky Lagoon incident, both X and Zero were assigned different missions to gather information about Repliforce's coup and to cut off their support lines. Iris assisted Zero on his missions as being his operator, like during the Erasure incident. However, Iris herself was part of Repliforce while her brother, Colonel, was Repliforce's second-in-command and therefore an imminent target for the Maverick Hunters. When the two of them battled in the Ceremony Hall of Repliforce's command center, it was Iris who stopped the two Reploids from terminating each other by begging her own brother to stop, since Zero had previously saved her life after the Sky Lagoon had crashed. Colonel, who had always regarded Zero as a friendly rival, backed off. Zero, on the other hand, stated that someone had to stop Repliforce at all costs, much to the grief of Iris. When Repliforce's coup began, Zero rushed to the space port to stop the ascension of the military troops to the newly constructed space station of Repliforce, Final Weapon. There, he battled Colonel again, this time killing him. After that, Zero traveled to Final Weapon where he was encountered by Iris, who was blinded by the grief of losing of her brother and anger for Zero killing him. She had salvaged Colonel's Control Chip from his remains, fusing it with her own programming, thus resulting her body to transform into a massive winged Ride Armor-like combat form which Zero was forced to battle. Even though Zero didn't mean to, he damaged the exterior power core of the structure, resulting in the destruction of the armor. He hurried to Iris' body. However, it was too late to save her, and while she lay dying in his arms, she whispers to him that she did all this because she wanted them to live in a Reploid only world. Zero, totally overwhelmed by her death, began questioning his own reasons for fighting.

Sigma would later antagonize Zero further, by revealing his involvement in the whole ordeal. He even taunts him by saying, "Iris is waiting for you!" before their battle.

After Final Weapon is destroyed, Zero flies back to Earth in an escape shuttle, but he is tortured by the thought of being unable to save anyone. Iris reappears as a memory as seen in Zero's ending in Mega Man X5, where an image of Iris is seen as Zero lay dying and all he can do is quietly apologize to her.

Rockman Online
In the upcoming Korean MMORPG, Iris appears working as a Navigator (along with Alia) for the UCA (United Continent Association) in the games first teaser trailer. As this games story is said to take place in the far future where the characters from both the Mega Man and Mega Man X series have long since passed away, this Iris (much like the other series robots and Reploids appearing in the game) is a copy/recreation, embedded with the DNA Soul of the original.

Quotes

 * "You are now on Laguz Island where the Erasure Incidents have happened. What's the situation there?"
 * "Okay. But please don't get too wild and bite off more than you can chew."
 * "X! Zero! We've just received..."
 * "Gareth... I can't find any data on such a Reploid in our database. Plus, we have found unfamiliar items..."
 * "They seem to have been resurrecting enemies by somehow utilizing DNA."
 * "It seems so. A Reploid's DNA is like that of a human's soul. From now on, let's call it a DNA Soul. We may be able to create something useful from Mavericks' DNA Souls."
 * "Wait a second. I believe the laboratory is a very dangerous place."
 * "Yes. I'm not going to stop you. Just please take this device. With this device, you can execute a Player Change at any time by pressing SELECT."
 * "Zero! Stop a minute and think about this! If you separate, you are walking into their trap. Why don't you fight together!?"
 * "Good job! You've cleared the game! If you save the data here, you can utilize the saved data for another mission. Please be sure to save and then try a new mission!"
 * "Great job! You have cleared two missions. You deserve a Special A level Hunter! But still I feel uneasy... I wonder if we really did restore peace. "
 * "X! Zero! The hollow Reploids are coming to life one by one!"
 * "Supreme job! Now that Sigma has been defeated, true peace has been restored. So now I have a present for you! This is an awesome mode where you fight against 8 bosses. How fast can you defeat them? Good luck!"
 * "Zero... Did you come to save me?"
 * "A huge Maverick appeared and..."
 * "My brother Colonel started the coup!"
 * "Please don't fight against him! This must be some kind of mistake!"
 * "Zero..."
 * "I've got a message from Repliforce..."
 * "Don't go Zero! Don't fight him!"
 * "Please stop, brother! ...Zero!"
 * "Stop! Please! Brother, please! Don't you remember?! Zero saved my life!"
 * "Zero, please don't fight with my brother! If you do I'm afraid that one of you might end up..."
 * "Zero!"
 * "Repliforce is at the space harbor..."
 * "No! ...Please wait Zero! I don't want to see you two fight..."
 * "So you fought with my brother..."
 * "Then it's over. Everything..."
 * "Good bye Zero..."
 * "Okay, I'll do it."
 * "Forgive me, Zero!"
 * "Stay with me, brother..."
 * "Please... stay away from Repliforce. Let's live together in a world where only Reploids exist..."
 * "Yes, I know... but I wanted to believe it... I wanted to live in a world where only Reploids exist. With you..."

Trivia
Iris is somewhat related to Roll from the Mega Man classic series.