Skate - Christ Air

Coffin:
Do a Double Grab then press Circle.

Dem Bones:
You can unlock a hidden character called Dem Bones by breaking each bone in your current character's body three times. Check the injury log to peek at your progress.

Frontflip:
Grab and move the Left Analog-stick Down or Up.

Rocket Air:
Hold L2 R2 Right Analog-stick Down.

Best Buy clothing:
Press Up, Down, Left, Right, Square, R1, Triangle, L1 at the main menu.

All characters:
At the main menu, press L1, L2, R1, R2, Down2, Square, Triangle to unlock all characters in Free Play and Party Play mode. If you entered the code correctly, a message will appear.

Best Buy clothes:
At the main menu, press Up, Down, Left, Right, Square, R1, Triangle, L1 to unlock all Best Buy clothes.

Plan B Warehouse:
Successfully complete Ryan Gallant's Pro Challenge to unlock Plan B Warehouse.

Play as Dem Bonez:
Break all of your bones three times in the injury log to unlock Dem Bonez. You can check the injury log in your backpack to see what you need to break and how many more times you need to break it. An easy way to do this is to go to the Mega Ramp at the X-Games arena. Veer off to the right of the Mega Ramp at the bottom into the street area doing a Christ Air.

Avoid crashing from falls:
Use the following trick to avoid crashing when you are falling from extreme heights. Just before you are about to land, hold L2 R2 to land instead of crashing.

Luge:
To luge, find a steep hill, and the perform a "Coffin" L2 R2 Circle. You must have speed or you will not go far.

Luge course:
At the top of "Old Town" according to the map, on the road with a wall on one side is a big cement dip on the opposite side with an entrance on the left and right. These are the starting points of a series of tunnels and branching open areas checkpoints for a giant luge course. Note: Make sure to set a starting point at the beginning because it is long.