You must finish a mission without dying after collecting a card to keep it. The "Paper Thin" Card
If you are looking for "paper" related to Metal Slug Advance , you are likely referring to the game's central or the specific high-difficulty Paper Thin card . The Card System
Unlike other games in the series, Metal Slug Advance features a card collection mechanic that serves as the main progression hook.
Obtaining this card is necessary if you want to unlock the Decoration card .
When active, your character (Walter or Tyra) will die in a single hit .