Ths is the final level and it is zero gravity. Use Triple Blade or Water Shield on the Moles.
Everything is also upside down.
That M-Tank is actually a W-Tank.
Guide your Commando Bombs to hit it or you can jump high enough to shoot them.
This is an E-Tank and an M-Tank.
Arm your Chill Spike to fight the final boss.
There are two Dr. Wilys. One is real and the other one is fake.
You want to attack the real Dr. Wily with Chill Spike. This is the only time the blob actually does damage instead of the spikes. These five orbs home in on your current location so use your zero gravity to avoid them as much as possible.
The big orbs are passed between the real and fake Dr. Wily. It has a tricky pattern.
As seen here.
With enough E-Tanks you can survive this fight and defeat Dr. Wily once and for all. At least until the next game.