Mega Man 4 Cheats

Mega Man 4 Free Pharaoh Shots
To kill with the Pharaoh Shot without using energy, power up a shot, then hit something while the shot is still building. Press Start then resume play and power up the shot again. Repeat as needed.

Mega Man 4 Secret Weapons
In Dive Man's level,after beating the second whale, there should be a hole nearby. Fall in it and dodge all the spikes to find the Wire Power. This power allows you you to hang on the ceiling and hit enemies for fair damage.

In Pharoah Man's level, instead of entering the first hole, use the R.Coil to jump over it. Go past the desert to find the Baloon Power. This allows you to release balloons that you can jump on.

Mega Man 4 Boss Sequence
The order you should defeat the bosses in:

Toad Man
Bright Man
Pharaoh Man
Ring Man
Dust Man
Skull Man
Dive Man
Drill Man