Better than Original, But Still Lacking
The first Prototype was an interesting game with an intriguing premise but a wealth of problems. Visuals got ugly quickly and the game became insanely difficult (worse than Red Faction Guerilla, which was infamously rough). Your protagonist, Alex Mercer, was thoroughly unlikeable and his powers were OK but the game wasn't really tailored around his abilities. They were hoping to emulate Hulk: Ultimate Destruction but it was not nearly as good (heck, not as good as the good, but not as great, Hulk game this generation from Sega).
In Prototype 2, you are James Heller, a soldier whose family was killed and you are hunting down the first game's protagonist, Alex Mercer, who unleashed a virus upon NYC. The story doesn't go more in depth and doing the side missions of taking out assorted scientists and generals doesn't really do much to further flesh out the story. You will do a lot of side missions and it just doesn't seem to have any point. You can consume people and take over their identity to sneak into areas, but if certain storyline missions require you be one specific person --- you will become that person, no matter what person you consumed most recently. And, yes, the consuming of people is still suitably gross.
Mercer gives Heller his powers (the reasoning still makes little sense), but you do feel, IMO, far more powerful here than in the original title. A lot of the powers were the same from the original title, but the game seems to be designed to make your powers so much more useful here). You get five powers, two of which can be mapped to face buttons at any time. You can jump insanely high, glide for long stretches of time, run faster than anybody else...you do have more than considerable power to handle the assorted challenges of the game in the, roughly, 14 hours of gameplay contained. That's 14 if you do everything. If you just do the main issues, it'll be less than half of that amount.
There are, of course, a lot of collectibles, but to make it more palatable, the collectibles do help you. If you find all of the blackboxes, or underground lairs, or assorted strike teams to wipe out, you do get major upgrades to your powers, overpowering you further. They are hidden well, but you will definitely want to collect them all because, before you try to beat it on the hardest difficulty in New Game+, you want to be thoroughly powered up. True, being totally powered up makes the game fairly easy, but without it, the difficulty on hard can be a significant challenge. It is, true, one of the easier hard modes out there, but still.
The game still has issues. Visually, while better, it is still rough. Draw in distance is not all that great. Enemies don't look all that great. It looks better than the original, but not better enough given how much time and how much better stuff has looked since Prototype entered the gaming market. The frame rate doesn't chug, even with a lot of mayhem on the screen, but the visuals are just so muddy that it appears they set the game as they did to explain away the engine's deficiencies.
I did enjoy the game, but it is one of the more bland games out there. It's fun, but before the month is over, you'll forget all about it. It is an absolute rental, but as a buy --- that is a stretch.