Unlockables
1) National Dex
Complete the main storyline and then leave your house after the credits, Cedric Juniper rewards you National Dex.
2) Wallpapers
A) First 4 wallpapers is Reshiram, Zekrom, Monochrome and Team Plasma. First 4 wallpapers unlocked until you complete the main storyline.
B) Last 4 wallpapers is Munna, Zoroark, Subway and Musical. Last 4 wallpapers unlocked until you enter the hall of fame.
3) TM95, Snarl
Give Mr.Lock the Lock Capsule to obtain TM95, Snarl. All Dark-type Pokémon can learn this move.
4) Trainer Card colour change
The colour of the Trainer Card changes when you:
Completed the main storyline, 49 streak in both Super Single and Double Subway lines in Battle Subway, Obtain all Entralink powers, Obtain all Pokémon Musical Items, Complete the National Dex
5) Birthday Cake Prop
Your birthday is set in your NINTENDO DS. When today is your birthday, talk to the owner upstairs and he give you Birthday Cake Prop. If this game is on NO$GBA, you can't obtain this prop at all.