Unlock Sudden Death Survival
If you want one-hit kills in Survival mode, all you need to do is survive through nine fights in Survival Mode and you'll unlock Sudden Death. Be careful though, as you can also die via one hit.
To make it so you or your opponent cannot block attacks in Survival and Versus, simply gain first place in Arcade mode.
To make your opponents much harder to defeat, complete Arcade mode once without continuing.
You can unlock a one-hit knockdown mode in Survival and Versus by getting first place in Sudden Death mode.
If you want your moves to move faster, win 100 battles in Survival with a single character, then record your name in the records.
Unlock Low Speed Mode
If you want to move in slow motion gain a ranking with each character in Arcade mode.
To always play in Hyper Beast Mode, win 10 fights with a single character in Arcade mode and record your name.
In this mode, the first character to fall will loose, but they will be invincible to all other attacks. To unlock it, win 20 rounds in Survival mode with a single character.
Win four rounds in Arcade mode without continuing, then defeat Kohryu in round five. You will then be able to play as him.
Complete Arcade mode without continuing once, then Uranus will appear. Defeat him to play as him.
From the main menu enter the options menu. Once you're at the options menu press and hold L2 and hit the Circle button.