Mega Man X8 Walkthrough

Intro Stage: Noah's Park
After the cutscene, head right through the jungle. Destroy any Beeloids (bees) you see with shots and grab the Metals. Cross the river when you get to it and destroy the Magnumis (missle Reploid). Continue right, destroing the Beeloids and groups of Magnumis. Soon you'll get to a small lightbulb-like enemy called a Bulbrite powering itself up using a Beeloid. Destroy all these enemies and collect the Metals. Continue right, and you'll go through a few earth tremors before encountering the Maverick that you will constantly fight in this stage: Intrusion Crabz-Y.

Dynasty: Gigabolt Man-O-War
This stage is all about chasing Gigabolt Man-O-War (who is in a UFO form) through a futuristic city while on a floating Ride Chaser. During the stage, you'll encounter glowing billboards. Don't hit them, as you'll lose speed. Instead, let Gigabolt hit them. The billboards will collapse if he hits them.

Gateway: Sigma
From the hangar bay, head right and enter the doors. You'll find a huge gold structure with teleporters on it. Here are the colors of them and where you'll find each Maverick (after you defeat them, you'll find out that they were fakes): After you defeat them all, you'll have to evacuate. Return the way you came, watching out for the crumbling floor. But when you reach the hangar bay, Sigma will appear. He'll talk a bit, then attack. Sigma has many attacks. One is Sigma Slash, where he'll do a dash slash.
 * Black: Dark Mantis
 * Red: Burn Rooster
 * Orange: Earthrock Trilobyte
 * Purple: Gravity Antonion
 * White: Avalanche Yeti
 * Cyan: Gigabolt Man-O-War
 * Yellow: Optic Sunflower
 * Green: Bamboo Pandamonium