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. It was attacked by Mavericks on point 5567 and destroyed. The Maverick Hunters pointed the blame on the Repliforce army due to their presence in the attack and refusal to cooperate. In reality, it was Magma Dragoon, a member of the 14th Unit, who after falling under Sigma's influence destroyed the power source from Sky Lagoon, resulting on its crash on a city below and many casualties. This incident set into motion the chain of events known as 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.