Mercurian Fortress: Mercury
Neptunian Seabase: Neptune
Martian War Stockpile: Mars
Venusian Tunnel System: Venus
Midpoint Battle: Dark Moon
Jovian Storm: Jupiter
Description of stage: This is a large space station made to monitor Jupiter's weather. The Stardroids want to control the station.
Saturnian Gravity Warp: Saturn
Plutonian Cavern: Pluto
Uranian Trap: Uranus
Confrontation with Terra
The Wily Star
Stage 1: Outer Space
This stage is unique as it is basically a shoot-em-up.
Stage 2: Old Foes Rematch/Teleporters/Cyberspace
Final Stage: Wily's Machines and Sunstar
This is the final stage. Collect all the items here, then drop down the long shaft. You'll meet up with Proto Man one last time. Collect his item, then enter the teleporter to face the boss: L. Knuckle and R. Knuckle. First you fight the left knuckle. Avoid it as it moves around while charging up the Mega Arm. When it punches the ground, release the Mega Arm at its eyes. Do this 7 times. Now it's time for the other knuckle. This one is faster, and it can both grab and fire missiles. Do the same thing you did to the first arm.
Now you face Dr. Wily in the Brain Crusher. This machine is unmoving, so you don't have to worry about bumping into it. Shot the Alabell bombs back to it to cause damage. After defeating the first form, the ceiling will become smaller and Wily will be visible. Shot where Wily to defeat him. After this, Wily activates the final boss: Sunstar.