Mini-Games: Hyper Difficulty:
You must win or tie 5 rounds in a row during a ''Who's The Best?'' mini-game championship against 3 CPU's on hard difficulty to unlock hyper difficulty mode.

Dodrio Game Boy:
Dodrio Game Boy speed - Complete Pokemon Stadium round one.

Use Mew I round2:
First Beat Round1 and then when you Unlock R2 you can use Mew as a rental in R2 Prime Cup Battles.

Surfing Pikachu:
Put the Pikachu you started with in Yellow in your party for Round 2 Prime Cup Master Ball. You MUST USE THAT PIKACHU IN EVERY BATTLE of Round 2 Prime Cup Master Ball. After you defeat the final trainer, your Pokemon will be put in the Hall of Fame and Pikachu will learn Surf! You can now play the Surfing Pikachu Minigame in Yellow version as well.

2nd Title Screen:
Beat R1 Mode, and reload the game. In place of the title screen is a new one.

Change your Pokemon's color:
If you nickname your Pokemon in the Gameboy game and bring it into Stadium, it will have changed color depending on what you nicknamed it! This has NOTHING to do with shiny Pokemon, because they were not invented when Stadium was released. Possibilities range from an orange Pikachu to a seagreen Tentacruel.