I've got a soft-spot for puzzle-platformers, especially when they dare to bring new gameplay mechanics to the table. Ever since I first got a glimpse of indie developer Strange Loop Games' upcoming title called Vessel, I've been pretty excited by its Steampunk aesthetics. Underneath that excitement was a cautious optimism about how successful the developer would be in designing puzzles around the game's extremely-cool liquid-physics systems.

This past week, I had a chance to spend some time with a PC demo build of Vessel, and played through the first of the game's two acts, which are broken up into five chapters apiece. I was introduced to protagonist M. Arkwright, an inventor responsible for creating simple, liquid-based creatures called Fluros. These Fluros of varying types were made to help run the world's vast stretches of machinery. But at the start of the game, they've begun to misbehave. It becomes clear that it's up to the player to figure out what went wrong and get the Fluros in-line so that they do their jobs, as intended. Naturally, it's an undertaking much easier said than done.

The first act of the game serves as a tutorial. Arkwright is pretty good at running and jumping, and is also able to grab and interact with various switches and levers across the world. Water was introduced almost immediately, and as it happens, turned out to be one of the most fun implementations of liquid-physics I've ever seen in a game. It sloshes around the environment fairly realistically, pooling and separating, appropriately. Many of the game's early puzzles task the player with things like redirecting streams to trigger switches that will open doors, and it's a fun enough system that even some of the more basic puzzles are fun and rewarding to solve.

As with any puzzle game worth its salt, Vessel introduces new mechanics at a gradual pace, and then asks players to use the suite of accrued tools in more complex endeavors. Turbines can be filled with water (or presumably other liquids, later on), and then activated to create Fluros which will help the hero by doing things like pressing remote switches. Fluros will come in some other flavors, such as Fluros made of lava that create great clouds of steam when they came in contact with water. (They're also harmful to bump into, unlike their watery counterparts.)

Many more tools of the trade were also introduced. Not long into the demo, I was tasked with building a water-pack device for Arkwright, which allowed him to vacuum water into a tank on his back, or aim and fire it--useful for cooling down the molten lava I would soon encounter, or filling various reservoirs to complete puzzles. Arkwright also must solve an early puzzle that gives him the ability to deploy "water Fluro seeds," which are basically dehydrated versions of Fluros that don't require a turbine to produce. Just add water. These "seeds" have ancillary uses as well, as they have a magnetic affect on nearby water, allowing the player to redirect streams of liquid.

Vessel also has a Metroid-vania style level design, in that you'll encounter hub-like areas with branching pathways to different puzzles, meaning there's usually something else to focus on if you get stuck on a particular conundrum. This is a good thing, because some of the puzzles span the entirety of giant rooms with multiple moving parts. Often I would enter a new room and spend several minutes just trying to make sense of it--exactly the kind of experience I look for in good puzzle games. Descriptive journal entries appear to describe new mechanics or story as the game moves along, and though I breezed through the puzzles in the first act of the demo, the second act served up some real head-scratchers.

In short, I'm very much looking forward to the full version of Vessel. The liquid-physics-based puzzles are refreshing--sometimes exhibiting a delicious complexity--making it a game that fans of new puzzle types should really consider keeping an eye on.

Vessel is scheduled to hit Steam as a digital download on March 1 for $14.99. Releases on Xbox Live Arcade and the PlayStation Network are also "coming soon."