Level skip:
Press Start to pause game play, then press B to advance through any level that was previously played.

Invincibility:
Successfully complete R-Type DX using ten or less credits. Then, press Select + A during a R-Type Standard type game.

Quick reset:
Hold B during game play and power the Game Boy off and on while continuing to hold the button. The game will resume at the start of the last level played with five lives but no points or power-ups.

Drawing mode:
Successfully complete the game in R-Type I Enhanced, R-Type II Enhanced, and R-Type DX. Press Right at the game type selection screen until the De Souza drawing editor option appears. Then, press Start to begin.