Mega Man 4’s passwords are very similar to the previous two games except that they do not remember how many Energy Tanks you possessed at the time you got the password. Such a shame, as storing this number is as easy as adding one more dot to the grid.
The password scheme works like this: There are ten items that the passwords record: eight Master Weapons, and two Adapters. Capcom paired these items into five groups of two items each. Each pair has only one dot on the grid associated with it. For each pair, there are four dots possible: one of the items acquired, the other acquired, neither acquired, or both acquired. Here’s the chart.
Weapon/Item Both Neither One Toad Man: Rain Flush A1 A2 B1 Bright Man: Flash Stopper A1 A2 C2 Weapon/Item Both Neither One Pharaoh Man: Pharaoh Shot A4 A3 B4 Drill Man: Drill Bombs A4 A3 C3 Weapon/Item Both Neither One Ring Man: Ring Boomerang B5 A5 B6 Dust Man: Dust Crusher B5 A5 C5 Weapon/Item Both Neither One Skull Man: Skull Shield E2 D1 F2 Dive Man: Dive Missiles E2 D1 E1 Weapon/Item Both Neither One Wire Adapter F3 E3 D4 Balloon Adapter F3 E3 D3
Now, before the password will work, you need to add one more dot. This dot stands for how many items/weapons you have, total. There are eleven possibilities for this final dot: ten items plus one dot for no items. Here’s that chart:
| 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 |
|---|---|---|---|---|---|---|---|---|---|---|
| F5 | A6 | B2 | B3 | C1 | C4 | C6 | D2 | E4 | E6 | F1 |
So to construct a password, punch in the dots for which, if any, of the Adapters you wish to possess, and which Master Weapons you want to have (the stages related to those Robot Masters will be completed, of course). Remember to double up the dots into the single dot when necessary, and don’t forget a single dot for the number of items you possess. At this point, you are done; there’s no way to skip Dr. Cossack’s fortress and go on to Wily’s. Sorry.