Disclaimer: I won my copy for free in a raffle for this game.
Progress at the time of this review: 24/47 Achievements, finished on Normal; this is my second RE game, the first being RE1 remake (reviewed here ).
Rating: 2/10; why am I even wasting my time venting
Verdict: I loved the fixed camera angles and the scarcity of resources in RE1. While these two aspects remain the same in RE0, the other changes RE0 made to the core mechanisms brought out the worst in the two.

Positives:

• Switching between controlling two characters on the fly is fun! Well, for the most part anyway. Giving the two playable characters each unique traits so that many puzzle-solving actions can only be performed by one specific character adds an extra layer to the puzzle aspect of the game, and while the puzzles themselves are very similar to RE1's, which I found mediocre, switching between characters to solve these mediocre puzzles made it more enjoyable for me by a surprising amount.

Negatives:

• The most frustrating part of RE0 for me is some of the enemy designs. Some of the enemies really belong to an action game rather than a game with such limited maneuverability. Some examples:
  
  • The Giant Bat . It's simply not fun to fight an enemy that literally flies in circles around the character when the game features fixed camera angles and scarce ammo, not to mention the swarm of smaller bats thrown in for good measure to make the already miserable aiming controls even worse.
    
  • The Queen Leech . The AI for the player-controlled characters does a terrible job of self-preservation, but I honestly find it serviceable throughout the game—until this fight. To have this enemy's attacks focus on the AI-controlled character who happens to have to stand for extended periods of time while relying on the other character to distract the enemy, while also making said enemy not reliably distracted every time the player-controlled character shoots at it (Did I mention how scarce the ammo is?), is simply a recipe for disaster. I had to take a week-long hiatus from gaming altogether because I was burnt out by the frustration.
• RE0 managed to mess up many core mechanisms that worked ok in RE1. Some examples:
  
  • Inventory and saving. I can almost accept the change where heavier weapons take up two out of the six precious inventory slots, but the removal of Item Boxes does far more damage than good. Now whenever you want to retrieve an item, instead of the easily navigable UI of the Item Box, you have to try to make the character stand at juuuuust the right spot facing the item and pick it up from the ground, not to mention that it's possible for an item to not be visible from any of the fixed camera angles.
    
  • Saving. Thanks to the removal of the Item Boxes, the players no longer have easy access to the Ink Ribbons next to each Typewriter. Instead, there are three obvious choices:
    
    • waste an inventory slot to always carry the Ribbons, which is utterly useless except on a Typewriter,
      
    • backtrack to where you left the Ribbons previously each time you want to save, or
      
    • ignore the Ribbons left on the ground earlier, which isn't even always an available option, since you may not have acquired new Ribbons yet.
• Maps. Whatever happened to the ability to view the maps of an area different from the one the character is currently in?
  
• The overall writing is marginally better than RE1, but it's in the same ballpark. Rebecca's character archetype (not to mention her suggestive alternative outfits) turned me off, but I was relieved that at least there isn't any forced romance subplot between the submissive heroine and the strong hero.