Water is a third person puzzle solving adventure type of game with an unique look and gameplay. It's a story about a mermaid, and fish men who aren't fish men. A story that brings you into tears and fears. It's about fish people, harp instruments, swimming, and crazy priests.
Water is truly a fresh breath amongst the huge bunch of typical Source Engine mods.
This mod simply has nothing at all to do with Half Life 2. It is so well designed that you'll only think "Ahh yes, this is the source engine" once or twice during the mod, so it could just as well have been a stand alone game. Calling it a mod is simply wrong, "game" is a more fitting term.
The game takes on a cool approach. Water, that is usually avoided in games, is now the only valid path for you. The player will experience all kinds of neat tricks that fit into this thinking, making the game feel really well planned and thought through before being made.
Water will show you a few new ways of interacting, using the source engine in ways I've never seen before. This is all great, and these new ways of interaction enables Water to challenge the player with some great puzzles. The puzzles require a bit more thinking than the typical game today, but still do not feel annoyingly difficult.
Graphics vise Water is a work of art. Through clever coloring the world above the water is grey and dead, but seen through water it's still beautiful. Tricks like these show that the good old source engine can still surprise players even though it might be somewhat outdated.
Of course the mod has some minor flaws. The story is great, but I found it somewhat strange, and not really helpful in solving any of the puzzles. A few times you might get stuck in a puzzle because of some glitch, but since the mod was just released I guess this is how things are.
Even with these flaws I couldn't get myself to rate this with only 9. Water is truly a 10/10 compared to other mods out there.