Not A Portal Reference

Not A Portal Reference is an achievement from the video game 'Splosion Man on the Xbox Live Arcade.

Achievement Description
Collect all 47 cakes in Single Player mode.

How To Unlock
Just as the achievement description says, collect all 47 cakes in Single Player mode. There is one cake in every level except the three boss levels.

Trivia

 * Despite its title, Not a Portal Reference is indeed a reference to the video game Portal.