Now we're in Wily's domain. Time to teach him a lesson YET AGAIN.
This is a pretty straightforward stage (most levels in this game are, if you haven't figured out already.)
The main challenge comes from a vertical fall into the heart of Wily's Fortress. Dodge the spikes as you go down, using the Rush Jet to alleviate the difficulty. Apart from the spiky column, it's not too tough a level.
A dragon boss waits at the end of the area. To beat it, dodge the shots, hop on the platforms it shoots out, and nail it in the eyes with Yamato Spear. Just be persistent, and it's not too hard to beat this beast.