Two player versus mode single only:
Hold L1 + L2 + Square, then press X at the map selection screen.

Double attack power single only:
Successfully complete all 64 normal and hidden levels.
Then, hold R1 and press X at the map selection screen.

Xenon Unit single only:
Hold L1 + L2 + Circle, then press X at the map selection screen.

Extra Goodies Battle Test:
Successfully complete all levels in main and original modes, then enter BATTLE as
a password.

Single Scenario mode:
Successfully complete all levels in main and original modes to unlock this option at
the main menu.

Main Campaign passwords:

Level - Password - Bonus
1 RANDAL LADNAR
2 HUNDRA ARDNUH
3 CINBER REBNIC
4 MARLIN NILRAM
5 BAYARD DRAYAB
6 WEBLEY YELBEW
7 PARKER REKRAP
8 MERKEL LEKREM
9 ITHACA ACAHTI
10 BAIKAL LAKIAB
11 SAVAGE EGAVAS
12 VALMET TEMLAV
13 MAUSER RESUAM
14 KIMBER REBMIK
15 BISLEY YELSIB
16 MEANEC CENAEM

Original Campaign passwords:

Level - Password - Bonus
1 REVOLT TLOVER
2 ICARUS SURACI
3 CRYANO ONAYRC
4 RAMSEY YESMAR
5 NEWTON NOTWEN
6 SENECA ACENES
7 SABINE ENIBAS
8 ARAIUS SUIARA
9 GALOIS SIOLAG
10 DARWIN NIWRAD
11 PASCAL LACSAP
12 HALLEY YELLHA
13 BORMAN NAMROB
14 APPOLO OLOPPA
15 KAISER RESIAK
16 NECTOR ROTCEN