Vessel is a physics-based puzzle game with a concentration on fluids, and is best characterized as interesting, charming, and frustrating. You play as a scientist/inventor who created Fluros, creatures made out of liquids.
Vessel presents you with puzzles which revolve around the idea of fluid interaction. Later in the game you encounter lava, so you must pave your path by cooling the lava with water. In some cases you need to make water flow against gravity by using Fluro seeds, which also allow you to create Fluros. Many puzzles are often solved using Fluros; they can move and jump around. They are also capable of pressing buttons, so you can create them if multiple buttons need to be pushed simultaneously in order to solve the puzzle. The puzzles themselves are actually pretty clever and become progressively challenging, as one would expect from such a game.
The game has a simple, pleasant art style. The overall quality of both the art and the animation shows that the developer didn't have a very large budget, yet clearly did the best they could with what they had. Ultimately, it adds to the feel of the game. It looks nice is my point. The journal entries have a very authentic journal-look to them and I actually really appreciate that in games (see: Uncharted 2).
I think where Vessel really stands out, at least in terms of presentation, is with its dynamic soundtrack. Essentially, as you progress through a puzzle's solution, layers of music are added on top of the base track. Not only does it sound fantastic when you've unlocked all the layers, but it also acts as a feedback mechanism. A new layer signals that you've done something right and that you're one step closer to completing the puzzle.
I've established that Vessel does a pretty good job at output. It doesn't look bad and clearly the soundtrack appealed to me. The puzzles are fun to solve and there's a nice look and feel to the game...except one thing.
Where Vessel fails, I think, is at input. In a game where the only way to solve puzzles is to move your character around within his environment, moving that character should never be an issue. Yet controlling my character through the levels, often having to jump between platforms, was an exercise in patience. There were many instances when I had mentally solved a puzzle (or at least a specific part of the solution) but had a rough time physically solving it solely due to shoddy controls and collision detection.
I think Strange Loop Games had a lot of nice and genuinely cool ideas that were decently executed. For the most part Vessel is fun, creative, and deals very well with fluid dynamics (congratulations to the programmer[s] responsible). It's a shame that such a crucial component of the game is executed so poorly. However, as the new studio's first product, Vessel succeeds more than it fails and shows that the studio has the potential to make a truly fantastic game in the future.