All weapons:
Enter DLVTRKBWPS as a password.

Unlimited lives:
Enter DLVTRKBLVS as a password.

Unlimited energy:
Enter DLVTRKBNRG as a password.

Bird mode:
Enter DLVTRKBBRD as a password. Hold Select and press A during game play to fly.

Level select:
Enter DLVTRKBLVL as a password. Pause game play and press A + B to advance to the next level.

Alternate end sequence:
Press Down in level 9 when the enemy appears. After entering the tunnel, shoot the computer and destroy the incubator. An alternate ending sequence will begin.

Hint: Get powerful weapons:
Enter QVZLBVSQLV as a password and play the game under the medium difficulty setting. Intentionally lose all lives, then re-enter the same password. Begin game play under the easy difficulty setting, then intentionally lose all lives. Begin a new game under the easy difficulty setting, then collect the light burden. Your character will now possess the particle accelerator and the chain gun. Note: Collect the pistol on level 2 to get ammunition for the chain gun.

Level	Easy	Medium	Hard
2	DVYLWKVYNL	QVYLWKVYDT	DLTLWKVYYC
3	GRYLWKWVNR	TRYLWKWVNN	GNYLWKWVPP
4	DRYLSRWVRY	QRYLSRWVTS	DNYLSRWVPT
5	GVZLSRWQKZ	TVZLSRSQKB	GLZLSRSVPW
6	DVZLSVQKK	QVZLBVSQRL	DLZLBVSVVB
7	GRZLBVSQZY	TRZLBVBQKB	GNZLBVBQVL
8	DRZLBVSQGG	QRZLBVBQKS	DNZLBVBQVN
9	GVYNBVBQGD	TVYNBVBQRL	GLYNBVBQQD