It's safe to say that Assassin's Creed 2 set the bar very high for this series - a great mix of creative storytelling, good writing and excellent parkour and combat mechanics made it a real knockout of a game. Unfortunately, Assassin's Creed 3 falls short in pretty much every department. It's not a bad game, and there are a few improvements and new features that really stand out as amazing additions - but the flaws are so significant that it's hard to actually recommend this game to anyone other than enthusiastic series fans.
The biggest flaw is definitely that the game feels woefully untested. AC3 on the PC has a ridiculous number of bugs, from epileptic horses to menu freezes that make it impossible to proceed, and I've been encountering them in virtually every mission and quite often while just running around. There are also a lot of bewildering things that somehow made it past playtesting; I was killing bears with a hidden blade that was apparently coming out of my bare arm for quite a while before the plot got around to letting me have it, and at one point I was wandering around and completely by accident captured a British Templar fort, which replaced the flag and all the troops there with American revolutionaries... in 1770. In-game tooltips display at very weird moments, like a prompt telling you how to lower your notoriety at a time in the game when none of the methods described are available to you, and every cinematic has a prompt saying "PRESS E TO SKIP" plastered across the corner for the duration. You're also given no explanation or instructions for huge swaths of key game concepts. It's not just software bugs, basically - this game feels like the PC port was never tested at all, and that the testing they did do was mostly from people who already knew the game really well.
That extends to the writing, too. The story improves considerably around the halfway point of the game, but the early levels are plagued with scenes that drag on way longer than necessary, a weird fixation on narration and having characters describe things instead of showing them to us, and extremely bad pacing. Skilled voice actors do their best with lines like "what's true and what is aren't always the same," but there's just no saving a lot of these scenes, and the characters are mostly unlikable and uninteresting. We're given no reason to care about any of the characters until several missions into the game, and when we do finally meet our protagonist, our introduction to him is watching several scenes of mediocre voice actors monotone their way through extremely lengthy speeches in Mohawk. (I can't express how bad the Mohawk acting is, it's literally like hearing someone reading a technical manual.) The game is in serious need of an editor - things just move way too slowly, especially in dialogue and cinematics.
Gameplay itself isn't nearly so problematic, but still suffers badly from a lack of thorough testing. The developers made a big deal about the ability to pick up weapons on the fly, but I had trouble picking them up even standing completely still with no enemies around. The new lockpicking minigame is a perfect storm of unnecessary, no fun and unreasonably picky about precise mouse movement. I had problems constantly with getting stuck on the end of beams unable to move forward, having to realign to the precise right angle to climb certain objects, and attempting to climb impassable barriers that are completely indistinguishable from climbable surfaces. Combat is flashy (and extremely attractive), but is also reduced almost completely to a rock-paper-scissors game where each enemy requires one (and, barring exceptional circumstances, ONLY one) particular key combination to defeat. Several of the optional mission objectives are almost impossible to understand unless you've already played the level once. It's just rough, basically. The difficulty is a huge mess - I had no trouble taking on entire forts simultaneously from the very beginning of the game, but failed other missions constantly thanks to pointlessly capricious layouts for stealth sequences and unpredictable cutoff points for achieving secondary objectives. Even the historical hooks are almost completely ignored - aside from a few memorable (let's be fair, excellent) scenes like storming Bunker Hill, the actual history feels much more like a gimmick than an actual setting. One entire component of the game (the economic/crafting system) is only usable with an XBox controller and will freeze if you so much as move the mouse. A lot of the major components of the game feel like a rough draft, basically.
It's not all bad news, of course. The new naval sequences are outstanding, and the special dungeons (featuring several shipwreck levels and some cool Caribbean areas) are finely polished. The the antagonist finally starts directly interacting with the protagonist, their character interplay is by far the strongest part of the story, and both fun and engaging (although don't be surprised if you find yourself liking the antagonist considerably more than our hero). Graphically the game looks pretty great, and the new weather system is attractive (especially localized effects like fog). The nature areas look particularly good (and are massive!), which was a wise decision - colonial America was perhaps not the best choice for this series, considering its lack of gorgeous, huge landmark buildings to climb on, but the game seems to be making up for that by going for knockout natural environments instead. Although a lot of the previous installments' RPG elements are gone, the new hunting system is pretty engaging. Aside from lipsyncing and occasional clipping problems, animation is extremely high-quality across the board, especially in combat. The world is enormous, there's a ton of stuff to play around with and climb on. And I actually did find a couple (non-mandatory) minigames that were surprisingly fun, where you play old-timey board games in taverns. Some of the other details, like set decorations that only appear once or twice in the entire game, are clearly labors of love. There is some highly polished work in this game.
Overall, though, I'd only really recommend this game to people who are already in love with the series. I think it could have set new standards in a lot of ways, with some of the extraordinary detail work poured into the game - but with such major flaws, especially in such key parts of the game, a lot of the excellence in AC3 is totally overshadowed by the mediocrity. If you do buy it, though, stick with it - the game's flaws become much less glaring once you get through the opening third (around the time you get to visit the third game region, the enemies become significantly more varied, you have access to a much larger arsenal, the levels become less railroady, and the plot picks up considerably).
Pros:
-Excellent and exhilirating naval combat, action-cinematic levels and special dungeons
-Very attractive, if not revolutionary
-Pretty much anything you do out in the woods is great
-Combat is fun to watch
-The engine can support huge numbers of NPCs simultaneously (crowds are, well, crowded)
-It is still pretty fun, once you get past the slog of a first act
Cons:
-Mediocre story editing and script and very poor story pacing, especially in the first third of the game
-Mostly uninteresting characters
-Zero effort PC port
-Absolutely overrun with software bugs and continuity errors
-Combat is highly repetitive and often turns into infinite loops with guards spawning faster than you can kill or escape them
-Possibly the worst mandatory lockpicking minigame ever made (it's not nearly as bad with a controller, but it's maddening with a mouse, and purposeless either way)
-The setting is not well-suited to the more appealing gameplay elements
-There's a well-documented bug that completely prevents you from progressing past a certain point without an XBox controller, which wasn't fixed in the recent patches
-Way too much tedious waiting
