High Gravity
On the main menu press down down down down right left right left
Low Gravity
On the main menu press up up left left up up right right
Player Skulls Arcade Only
On the difficulty menu press up right down left up right down left
Savant difficulty
On 1P mode in Arcade on the difficulty selection screen press down 10 times and the cursor will move automatically under the Master difficulty and the game will automatically start in Savant mode
