I recently made the huge financial decision to drop $15 on Castle Crashers for XBLA, and I must say I'm very pleased with the results.
The game is in many ways an homage to old school arcade sidescrolling brawlers like the original TMNT or X-Men arcade games. At its core it's extremely basic - light attack, heavy attack, jump, magic - but it throws in a few key RPG elements and some fun combo-style gameplay, and it really helps to bring the sidescrolling brawler into the new millenium.
Of course, what with this being a game design blog, we're not here to review the game, we're here to tear it apart. The game is tons of fun and is in no way an incomplete package in its current form, but if we wanted to make it better, well, there are a few things that we can change.
The Spice of Life
The biggest and most obviously RPG-ish element of Castle Crashers is the fact that you level up while you play, gaining points to put in some basic stats: Strength, Magic, Defense, Agility. This is a great way to keep the game fresh as you play through, and a way to give your current character an identity and play style.
Unfortunately, it falls a little bit flat. Characters end up being similar as so few stats mean everyone is putting points in the same crucial areas. One of the more obvious instances of this is the fact that you don't gain any new magic abilities unless you specifically put points in your magic stat. This is intuitive and makes sense, but the problem is that, if you want to keep things as fresh and fun as possible, new abilities are key.
The problem isn't that you gain abilities by putting them in the magic stat, it's that you don't get them for putting them anywhere else. If once every 4 or 5 points you put into each stat you gained a new ability, it would really give each character their own identity as you leveled them a specific way. A few examples of said abilities would be something like a new combos/attack for strength, a last stand ability for defense (when HP is critical take less/do more damage), or a double jump for agility. They don't really have to be AMAZING, just fun and useful in some situations.
Up Your Arsenal
The weapon selection in the game is great, and there's a ton of variety and fun little things to be had here. Really the only suggestions I have for this are more, varied effects (stuff like crits and and elemental properties), maybe something like extra knockdown, a percent chance of instant kills, or even weapons that actually grant new abilities.
The other big suggestion I have is to change how the weapons attack. Obviously the issue here, with this sort of game, is that you have to create new hand-drawn animations for things to attack differently, but it would be cool if you wielded swords and maces differently, and they then took on different properties on attack (maybe even a different combo set).
The game is incredibly fun, and has a lot of replayability, but it would be great if there were more levels. Obviously this will always be true and any great game can always use more, but I'm imagining a world map not unlike Super Mario World, with lots of different levels, secret levels, hidden pathways, bonus levels, and the like. Of course, in a $15 game it's asking a lot to have this much content, but if they put out Castle Crashers 2 with all the above additions and a world this large, I'd be willing to spend a little more for the amazing experience it would undoubtedly be.