Can be played on Sons Of Liberty (with exception to NTSC-U), Substance, and the HD Edition.
Difficulties somewhat follow the Sons of Liberty NTSC-J naming convention:
“Easy” = Very Easy from most versions.
“Normal” = Easy from most versions.
“Hard” = Hard from most versions.
Extreme can only be accessed using the developer menu.
Final Score Screen time is always one or two frames less than what the player sees after the final hit on Solidus.
HD Edition increased the time it takes for grenades to blow up, therefore Stun Grenade strategies for the Tengu fights might differ a bit.
Load times, lag, and pausing the game using start do NOT count towards the in-game timer.
Menu-ing weapons and items do count towards the in-game timer.
Optimal strategies for boss fights in the main game does NOT always translate well to Boss Survival.
PAL50 should run at a lower framerate, therefore should result in a worse final in-game time.
Sons of Liberty (NTSC-J) has a slightly faster Solidus since you can hit the walls with the blade, cancelling the animation halfway through.
The boss fights on Sons Of Liberty and Substance Xbox NTSC-U include:
Olga, Fatman, Harrier, Vamp, MG-Rays, and Solidus.
The boss fights on Substance and HD Edition include:
Olga, Guard Rush, Fatman, Harrier, Vamp, Tengus, MG-Rays, and Solidus.
Two playable characters: Raiden and Snake.
Tengus can NOT be skipped using the Door Glitch, but can be skipped using the Coolant/Choke/Stun skips.