Second Controller Effects
Mega Man 3 contains some hidden effects which are revealed by using the controller connected to port two on the NES console, while still playing the game using the controller in port one.
- Holding
on the second controller causes Mega Man to jump much higher than normal. Also, if Mega Man should fall into a pit which would normally kill him, he will not die. Mega Man can still be controlled to walk left and right while in the pit, and can jump out to continue on his adventure. Furthermore, if this technique is used and Mega Man is in such a pit, releasing and then quickly again depressing can cause Mega Man's life energy to be reduced to zero, but he will not die. Instead, he can continue as before, but the game's background music will cease and Mega Man can take no further damage, in effect becoming invincible. This invincibility ends if his life energy increases, as by picking up energy power-ups or by using an energy tank from the sub-menu. If he should gain any life energy, he can once again be damaged by enemies as normal and will die if his energy is reduced to zero.
- Holding
on the second controller causes a strange slowdown effect, making the controls less responsive and slowing the sprite animation in the game. By holding with 
, sprite animation is stopped completely, and the controls become even less responsive.
Phantom Rush Jet
Normally, the Rush Jet is gained with the Needle Cannon after defeating Needle Man, but it is possible to use the Rush Jet before acquiring it in this way. After defeating Shadow Man, select the Shadow Blade in the sub-menu and then press 
. The Rush Jet will be selected, even though it does not appear in the sub-menu. The energy for the item starts at zero, so it is unusable until Mega Man picks up some weapon energy power-ups, but otherwise it operates just like the normal Rush Jet. After gaining energy for this item, it will appear on the sub-menu in subsequent stages, just as if it was awarded regularly.