Mega Man 2/Wily Fortress 5

Dr. Wily's Teleport System
Ahh, the infamous "you have to fight all the Robot Masters again" stage.

You'll start this stage in the Dr. Wily Teleport System room. Beat all the Robot Masters again the same way you did before. Shouldn't be too tough. For a few giggles, try throwing Metal Blades at Metal Man.

You cannot use all the weapons for these reasons:
 * Atomic Fire: save it for Dr. Wily phase 1;
 * Crash Bomber: mostly used up in Cannon Room, save the rest for Dr. Wily phase 2;
 * Bubble Lead: save it for Dr. Wily phase 3;

Therefore, use the suggested weapons (in green) as per the table below. The table lists all the damage dealt by each weapon (at the top) to each Robot Master (on the left). Data refers to the Western-NES "hard" mode, i.e. the normal mode in every other port of the game; for the Western-NES "normal" (easy) mode, simply double all the damage dealt.

Boss: Dr. Wily
Once they're all defeated, a ninth teleporting hatch will appear. Go through it to fight Wily's contraption. This battle has two parts, which are both relatively simple and similar.

During phase 1, simply hit the Wily Machine with two fully charged Atomic Fires. Otherwise, if the Atomic Fire is used up, load the machine with Metal Blades using jump attacks and diagonal attacks.

After the first life meter depletes the shell of the machine cracks off revealing Dr. Wily, and the life meter refills. Continue firing Metal Blades at him using a jump attack. If you defeated the Boobeam Trap (the previous boss) with one or two Crash Bomb remaining, during this phase try to get on the back side of the machine, and release the Crash Bomb directly on Wily as he is backing up. If placed correctly, you can defeat phase 2 in one hit. This is very hard to do and will probably require you to use 1 or 2 energy refills.