>>15809450
Get a X360 and all the games for it, the Sigma games run like ass on PS3 despite the downgraded visuals.
>Ninja Gaiden Black
Arguably the best game, it emulates just fine on a 360 (only the unlockable original NES games are unavailable due to licensing issues) and it's available digital for $10 in case you can't find a physical copy, highly recommend you play it on the original xbox with component cables and a CRT though.
>Ninja Gaiden 2
Unforgiving difficulty (black spider ninjas will spam explosive shurikens offscreen, ninja dogs will absolutely fuck your shit unless you abuse the best weapons in the game the lunar staff and the eclipse scythe, demons take half your lifebar with each hit and on master ninja difficulty they throw 5 or so annoying normal enemies alongside bosses), unstable 60fps, 15+ enemies at once and tons of blood and gore, Sigma 2 censors the blood and gore, massively tones down the difficulty by limiting the amount of enemies you can engage at once (5 onscreen, 4 offscreen, and they don't spam explosive shurikens as much) and shoves shitty Rachel/Momiji levels between Ryu levels that last too long and don't add anything meaningful to the story, 2 has overpriced DLC ($10 for a bloody palace-like mode, $3 a piece for every skin) in case you want all the achievements.
>3 Razor's Edge
Ryu at his craziest, the story is ass but who cares when you get to ogle big anime titties and fight cyborg dinosaurs, giant witches and attack helicopters? Razor's Edge adds a few levels where you play as Ayane, Kasumi and Momiji, but these are really short and the new girls play a lot faster than the blonde and the miko, avoid the vanilla game as it only has one weapon, one ninpo, your moveset is limited, you can't level up skills, the AI is braindead and the health bar is no longer visible, 3RE fixes all this, adds 8 weapons and 4 ninpos iirc, is a lot more gory, runs better than 3 (on the 360 anyway) and comes with all the DLC from the base game, they added new outfits for the girls and ryu but all of them are bundled in a single $5 package.
Avoid Yaiba Z entirely, it's the DmC of Ninja Gaiden.
>>15810707
It's alright, very short though, but for $10 i couldn't complain.