Review is based upon the latest patch for the PSVita (as of this writing - July 2016).
I hate "episodic" titles and half-baked games where you need DLC to experience the "full and actual" version of the games. But when this Vita port's case screamed "All Episodes+Extra Episodes" I knew I had to buy this one.
REvelations 2's story starts off sometime after the events of RE5 and REvelations 1 and just right about the events of RE6 - it's what the story indicates. Knowledge about the previous games are helpful but you can still start here from scratch. It stars RE2's Claire Redfield and RE1/3 supporting character Barry Burton(it's about time - yeah, go Barry!). Without spoiling the story too much, REv 2's story progression starts of tense until it gets cheesy in the end (in my opinion). The bad ending is worst where the story just abruptly ends. The depth of each character are decent. Each of them have backgrounds that ties in to the plot although out of the four characters, I found Claire lacking. There's something to like about the overbearing father Barry Burton and the rebellious and angsty Moira Burton. This father-and-daughter tandem swear a lot too. Natalia Kordia is pretty much similar from that girl in RE4 although she's way more useful and certainly not a deadweight.
The main game is divided into four episodes. This TV series-like exposition is first experienced in Revelations 1 but it's only here that the story itself is actually divided into four. After finishing the main game you can start from any episode. This is great for S-rank completionist and speed runners. Each episodes are divided into two - Claire's and Barry's. Tagging alongside are Moira and Natalia respectively. Finishing Claire's part of the episode will let you play Barry's part next. Barry's story takes place 6 months after Claire's story. And I kinda like the interaction between Claire and Barry's side of the story. This is reminiscent of Resident Evil 2. Although the paths are pretty much straightforward, certain actions you've done playing as Claire can affect Barry's path. This can open up alternate routes which leads to shortcuts or hidden items/weapon.
Gameplay is similar from previous games but you can acquire new skills that'll help you in the main campaign. It's still the same old third-person shooter. Puzzles are easy and much more grounded compared to RE1-4. There's a healthy dose of stealth here too. Pretty nifty if you aim to conserve ammo. While combat is sometimes inevitable, you can breeze more than half of the game just running away. Revelations 2 is almost a step closer to living up to its name as a survival game. Partnering with an AI is not as problematic as before since they seemingly cannot be killed(haven't experienced it yet). They rejuvenate health overtime and can be revived when they're incapacitated. The real problem lies with faulty AI. They get stuck(although rarely) and they're late to react.
Aside from the story campaign there are other modes to play from. Extra episodes "Little Miss" and "The Struggle" reveals part of the story missing from the main campaign and introduce specific gameplay not entirely found in the main campaign. There are also Invisible Mode and Countdown Mode. They're both main campaigns but set within specific conditions. Invisible Mode is where all enemies are initially invisible and Countdown Mode is where you race against time. There is also Raid Mode which is similar from Revelations 1. This is pure shooting fun and can be played solo or via internet/ad-hoc(only available in later patches). A leveling and rpg-like system is implemented but it can be a grind just to level up every each one of the characters so it's most likely you'll focus with 1 or 2 characters if your only aim is completion.
Extra contents includes rewards, raid rewards, CG gallery, secret files, movies, character models. So there are lots of stuff to do. Milk this cow dry.
But despite that, there are problems from making this game great. Since this is a port, it is understandable that there will be downgrades. The graphics are okay but other Vita games have done better. There are slowdowns, glitches and crashes. I've experienced four crashes. Although with the latest patch I've had only one crash so far. The latest patch cost almost a gig so it's problem for those with memory cards that are almost full. You'll miss out some raid mode content and fixes if you haven't patch up yet.
So, some good points and some bad points I can say for this game. But overall, I found this game satisfyingly good. 7 out of 10.