Note: This game is also titled Rockman X4.
 
Megaman X's Ultimate armor
At the player selection screen, highlight Megaman X. Press Circle(2),
Left(6), then hold L1 + R2 and press Start. Note: Hold L1 + R2 until
the game begins. Then, enter a special armor capsule to receive the
new armor. For the Japanese version, press X(2), Left(6), then hold
L1 + R2 and press Start. 

 
Zero's black armor
At the player selection screen, highlight Zero. Then, hold R1 and
press Right(6). Release all buttons, then hold Circle and press
Start. For the Japanese version, hold R1 and press Right(6). Release
all buttons, then hold X and press Start.


Unlimited lives for Zero:
Begin game play on the Cyberspace stage. Complete the first stage with a "S" 
rank. Collect the extra life, and repeat as needed. 


Unlimited lives for Megaman X:
Begin game play on the Frost Walrus stage in Area 1. Go to the section where the 
ice passages disappear. Turn to the left and get the extra life. Repeat the process 
to collect as many lives as needed.


Megaman's Ultimate Armor and Nova Strike:
Enable the "Megaman X's Ultimate armor" code. Play through the first two 
introduction stage, then start the Jungle stage. Go halfway down the second 
waterfall and go to the right. Enter the capsule and to get the Ultimate Armor along 
with Nova Strike and the aerial attack.


Animation sequences:
Begin game play and leave the game unattended for approximately ten minutes. 
Megaman and Zero's animation sequences will eventually being to play.


Capsule locations:
Information in this section was contributed by Ace99. 

Armor capsule
Go to Magma Dragoon level and proceed until reaching the part of Volcano Area 2 
where you have the armor. Get into it and dash jump towards the platform. Get on 
to the platform, then charge twin slasher to full power and destroy the blocks in 
front of you. Pass through and get the armor upgrade. 

Helmet capsule
Go to the Cyber Peacock level and get a S rank on the third stretch with the yellow 
balls that drains your energy. This is difficult to accomplish, but possible. 

Leg capsule
Go to the Web Spider level and proceed to the part with the waterfalls. When you 
drop down to the section below the part with the spike spinning on the platform, 
just go through the gap on the right side wall opposite to the hole. 

Arm capsule
Go to Storm Owl Area 2 with all the laser cannons. Get to the section with the hole 
in the ceiling, with spikes on the floor and each side of the wall. Use the lightning 
web weapon to jump onto the platform. Above it are two capsules. One allows 
your fire four shots in a row and the other allows you to fire a plasma bolt. The 
best choice is the plasma bolt, as it keeps hitting the enemy after the first hit. 

Ultimate capsule
Begin game play as Dark X. Go to the Web Spider level and proceed to where the 
leg capsule was located. Instead, you will receive the ultimate armor. This allows 
unlimited nova strike, unlimited none charged special weapons, hover in midair, 
and the ability to shoot plasma bolts. 


Defeating the Bosses:
Each Boss have a weakness related to their own weapons. 

Dragoon: Owl's weapon
Owl: Cyberpeacock's weapon
Cyberpeacock: Mushroom's weapon
Spider: Beast's weapon
Ray: Walrus' weapon
Walrus: Dragoon's weapon
Mushroom: Spider's weapon
Sigma In Ghost Robe: Dragoon's weapon
Sigma Out Of Robe: Spider's weapon


Recommended order and Boss weaknesses: 
The following is a recommended order for the Bosses, and their 
weakness (with Megaman X, followed by with Zero).

Web Spider: Twin Slasher (Slash Beast); Z-Sabre/Kuuenzan (Split Mushroom)
Split Mushroom: Lightning Web (Web Spider); Raijingeki (Web Spider) 
Cyber Peacock: Soul Body (Split Mushroom); Ryuenjin (Magma Dragoon) 
Storm Owl: Aiming Laser (Cyber Peacock); Rakuhouha (Cyber Peacock) 
Magma Dragoon: Double Cyclone (Storm Owl); Raijingeki (Web Spider) 
Frost Walrus: Rising Fire (Magma Dragoon): Ryuenjin (Magma Dragoon) 
Jet Stingray: Frost Tower (Frost Walrus); Hyouretsuzan (Frost Walrus) 
Slash Beast: Ground Hunter (Jet Stingray); Z-Sabre/Kuuenzan (Split Mushroom) 

Easy lives and energy:
Go to Frost Walrus/Kibatodos stage. Then, dash jump towards the first wall on 
your left, then dash jump to the right one. Continue to the right. You will see two 
snowmen. Use either the Lightning Web (X) or the Double Jump (Zero) to jump 
higher and reach the upper-right edge. Defeat the weak enemies here and get a 
lot of energy capsules. If you have not taken damage, you should have one E-tank 
full at 50%. You should also get the life near the appearing and disappearing 
platforms. Return four times maximum to fill up your two E-tanks and get a good 
supply of lives. Note : For really tough fights (for example, Colonel and Sigma) 
and you have already used all your energy tanks, it might not be a good idea to 
pick up many lives. However, do it against the eight Mavericks once you meet 
them again, if you do not use tanks during the fight.


As X, go to Snow Base level and at the area before the ice slopes, jump on the 
side of the wall and use the Lightning Web. Dash in air to the web and then to 
higher ledge that you cannot see from the ledge you were on. There will be 
several health units and weapon units located there. Collect and leave, then repeat 
as needed. 

As Zero, go to the beginning of Snow Base level. Double jump to a rock wall 
across from the wall behind you. Collect the lives and leave, then repeat as 
needed. Note: You can only get nine lives maximum.


  Game Shark Codez:
 
                   
  Infinite Lives           
  80172204 0002
                   
  Infinite Energy          
  80141924 2020
                   
  Infinite Lightning Web   
  80141970 3030
                   
  Infinite Leg Jets [Note] 
  8014199C 9D00
                   
 Note: Press X to turn the Leg Jets off.