Cheat mode
Press D-pad Left, D-pad Right, Analog-pad Left, Analog-pad Right, Square, Circle, D-pad Up, D-pad Down at the title screen. A sound will confirm correct code entry. The cheats, tips, artwork, and sound tests for all games will be unlocked.

Music player:
Successfully complete the game.

Art gallery:
Complete the indicated task in the listed game to unlock the art gallery for that title.

1941: Defeat the Krote, the level 4 Boss. 
Avengers: Complete level 4 and rescue the girl. 
Bionic Commando: Get over 25,000 points. 
Black Tiger: Defeat the level 3 Boss. 
Block Block: Complete an extended bonus. 
Captain Commando: Defeat Dr. T.W., the level 5 Boss. 
Final Fight: Pick up Eddie E's Bubble Gum. 
Forgotten Worlds: Complete three stages. 
Last Duel: Get over 100,000 points. 
Legendary Wings: Find a "Lucky!" hidden area. 
Magic Sword: Reach level 20 of the tower. 
Mega Twins: Enter the Monster Castle. 
Quiz & Dragons: Get over 200,000 points. 
Section Z: Complete Section E. 
Side Arms: Defeat the level 3 Boss. 
Street Fighter: Reach Thailand. 
Strider: Defeat Captain Beard Jr. in level 3. 
The Speed Rumbler: Successfully complete level 3 (Stone Hill). 
Three Wonders: Finish one the games. 
Varth: Defeat the Steel Golem in level 15. 

In-game Hints:
Complete the indicated task in the listed game to unlock the in-game hints for that title.

1941: Get over 500,000 points. 
Avengers: Get over 20,000 points. 
Bionic Commando: Complete level 1. 
Black Tiger: Get over 25,000 points. 
Block Block: Complete the beginner course. 
Captain Commando: Get over 30,000 points. 
Final Fight: Play as all three characters. 
Forgotten Worlds: Get over 15,000 points. 
Last Duel: Get over 50,000 points. 
Legendary Wings: Get over 30,000 points. 
Magic Sword: Get over 120,000 points. 
Mega Twins: Get over 15,000 points. 
Quiz & Dragons: Enter the Flatfield from level 2. 
Section Z: Get over 70,000 points. 
Side Arms: Get over 200,000 points. 
Street Fighter: Get over 60,000 points. 
Strider: Get the Terapodal Robopanther. 
The Speed Rumbler: Get over 20,000 points. 
Three Wonders: Play all three games. 
Varth: Get over 250,000 points.