Sky Lagoon

Sky Lagoon (スカイラグーン) is an aerial city that appeared as the Opening Stage from Mega Man X4.

Description
Sky Lagoon was a floating city stationed high in the sky at Point 5567. It was randomly attacked by a large number of Mavericks - the presence of Repliforce at the site made the Maverick Hunters suspicious, and thus they launched an investigation. X/Zero fought off the giant Mechaniloid Eregion before finding Magma Dragoon, a member of the 14th Unit, near the city's power source. He claimed it was too late to stop the city's fall before escaping, so X/Zero did the same. In reality, it was Magma Dragoon who was responsible for sabotaging the city and causing its fall, having succumbed to the influence of Sigma.

After the Sky Lagoon crashed onto the ground below, annihilating another city underneath it, X/Zero return to inspect the rubble. They confronted Eregion again and this time destroyed it, saving Iris. However, when Colonel appeared to check on Iris, they requested he disarm and come into Maverick Hunter custody for questioning. Colonel refused to be arrested and instead fled. This put Repliforce's role in the incident further into question, and became the last straw that caused the tension between the Maverick Hunters and Repliforce to finally explode. Soon afterwards, Repliforce announced their quest for Reploid independence and began the coup d'état leading to the Great Repliforce War.

Enemies

 * Knot Beret B
 * Knot Beret G
 * Kyunbyuun
 * Mad Bull 97
 * Spike Marl
 * Tonboroid S
 * Trap Blast
 * Boss: Eregion

Other Media
In the Rockman X4 manga, an unnamed city on the ground was attacked by Eregion like Sky Lagoon in the game, injuring Iris as a result. X, Zero, and the Maverick Hunters fight Eregion while Double goes to assist them. Eregion is eventually destroyed by X, and Zero saves Iris. As Zero hands Iris back to the Colonel, Double eventually catches up with a used piece of equipment bearing the Repliforce insignia on it, claiming he found it next to the corpse of Eregion. This causes suspicion to fall on the Repliforce as being responsible for the attack, especially when Colonel refuses to disarm while under investigation. This rampage is later said by Zero to have killed millions of people.