Perform a drop roll on all characters will mostly defeat them. Perform a drop roll will cause the character to stall and give you a few seconds to continue working on the enemy. Please check your instruction manual to practice and learn the move this will surely defeat your opponent.
In the game there are a total of 50 Challenge, 50 Sniper, 30 Stingray and 100 Honeycomb Lock mini-game missions and everytime you complete 10 missions in the mini-games a piece of art becomes unlocked.
I played Nina Story mode many times (about 5 or 6).
Unlocked Nina difficulty levels:
Beginner Normal Hard Expert
The 2nd time I played - at any level -, restarting from a completed save, I've got the bag to select Nina's outfits when I want.
The 3d time - at any level - I've got the wrestling outfit, one of the most gourgeous.
If You complete the game in Nina's story mode at any level, but with a final result of 5 stars rating, You can have another extra outfit (the last one I suppose), that's the Nina Tekken 2 Graphics figure.
If You play the Anna mode story (unlocked after You complete Nina's story at any level), and You finish it (I played it at hard difficulty, don't know if this is valid also for the others Anna mode story levels), You unlock Heihachi: that means that when You are playng with Nina story mode, and You have to beat the final boss, who's her sister Anna, the game shows You a new screenshot, where it ask You in, if You want to choose to fight vs. Anna or vs. Heihachi. If You choose Heihachi, You'll fight against him.
Another cheat I submit You is this, but I have some doubts (pls. Someone tell me anything about): I discovered and collected each time in Nina's Story Mode 28 golden coins. I'm not sure what they are for, somewhere I read they unlock more defribillators when You start a new game from a cleared file (I had at maximum 6 defribillators, each time I restarted Nina's story mode from a cleared file).
Unlock Easy Mode: Keep intentionally dying while playing the game until you recieve the prompt to play Easy mode.
Unlock Expert Mode: Successfully complete the game in Hard difficulty.
Unlock Heiachi: Successfully complete the game in Anna mode Heiachi to unlock Heiachi.
Unlock Unlimited Weapons: Successfully complete the game to get a cleared game file then start another game with the cleared game file and complete it opening the green weapons boxes in the following locations to collect the corresponding unlimited use weapons.
Unlock Katana: Cell 3 in solitary west access.
Unlock Railgun: Engine room on the ship
Unlock SMG: Dr Boskonovich's room.
Unlock 9mm handgun: Contraband room in the prison.
Unlock Tonfa Baton: Back of the heliport on the ship.
Unlock Suitcase gun: Under the stairs in the deep sea submarine pen.