Hints and tips
This section deals with some handy hints you might want to know about the game. Some people might consider some the information revealed below as spoilers (but most of the other guide sections contain spoilers anyway), so please don't read this section unless you've already been through the game or you truly want to know. Some information deals with the endings of the game, so read on with care.
| You'll only be able to use X from the beginning of the game, but you'll still be able to restore Zero as a playable character later on. Read on below if you want to find out how. |
| To restore Zero, you'll need to enter one of the secret boss rooms in each stage before beating all eight Investigators or before gathering 3000 DNA Souls. If you enter a boss room, you'll have to fight the Zero Nightmare. Once you defeat it you'll regain Zero as a playable character. |
| After defeating the Zero Nightmare, if you re-enter a secret boss room you'll fight against High Max. He'll be incredibly tough to beat, but if you defeat him you'll be able to go straight on to Gate's Secret Lab stages. |
| If you enter a secret boss room again after defeating High Max or after clearing out all eight Investigators, you'll battle Dynamo. If you use the Meteor Rain/Ensuizan on him he'll drop souls for you to pick up. Each time you go into a secret boss room from now on you'll fight Dynamo. |
| You can also skip to Gate's Secret Lab stages if you manage to gather 3000+ DNA Souls before defeating all eight Investigators. |
| Both X's Ultimate Armor and Zero's Black Armor can only be gained by using a secret code on the title screen. Refer to the Items Guide to find out more. |
| The levels and health of each Investigator will be determined by the order you fight them in. The first few bosses you fight will be low, but they'll increase as you progress. |
| There are three different endings for the game, one where you beat the game with X but haven't rescued Zero, another where you beat the game again with X but have rescued Zero, and the final is when you beat the game with Zero. |