Wetrix on the N64 is one of my favorite games on the system, and one of my favorite puzzle games in general. It tasks the player to use tetris-like blocks called "uppers" on a 3D plane to create retention for lakes, which will fill by rain and falling bubbles full of water. Any water not walled in will drip off of the edge, filling a drain that looks like a rain gauge. When that drain fills, it's game over, and time to see if your score ranked. Like most successful puzzle games, it sounds simple enough, but the game has its tricks to stifle your scoring, making it simple to learn, but a challenge to play at a high level.
Scoring takes place in two main ways. One, by retaining water in one or more lakes. A single water cluster falling into multiple lakes grants a multiplier. If water in a single lake becomes deep enough, a rubber ducky will appear, granting another multiplier. Also, if enough total volume of water is being retained at once, a rainbow appears, granting a massive 10X multiplier. This is great, but the real points come by having all or some of these set up, then dropping a fireball, which evaporates all water in one lake, giving off big time scores, which increase dramatically by hitting large volume lakes.
All of this creates a compelling dilemma between number of lakes vs size of lakes, encouraging different approaches to maximize score. However, there are hazards to work around as well beyond just dripping water. First and most importantly, there is an earthquake meter, which gradually fills each time you place a new land piece. If this fills up, a massive quake happens, which randomly annihilates most of your walls. To lower this meter, you can use "downers," which are downward arrows that will lower any piece of wall they touch to base level. These can also be useful for shaping your lakes. Also, bombs drop, which not only destroy what land they touch, but create a hole that must be plugged with more land. This lowers your earthquake meter, but must be fixed quickly. If a bomb falls diwn an existing hole, it'll drop three more, so be careful. Also, your fireballs can be used as bombs that don't make holes if you drop them on land instead of water. Lastly, as your level increases, floating bombs will appear, and if they touch bottom, you have a new hole.
So, yeah, that's a lot of compressed info, and the game eases you into it gradually. It also gives you a smart bomb if you achieve five lakes, which is a desperation move to essentially empty all meters and reset your land to flat while retaining your score. It's tough at first, but stick with it and you'll start putting up impressive scores in a hurry.
There are also challenge scenarios and a vs mode, in which good scores allow you to build up attacks to send at your opponent, but they are all direct variations on the classic mode, which is easily the most complete Wetrix experience.
My N64 cart is beat up, but it was free at least. Wetrix also came out on Dreamcast as Wetrix + and GBC in Europe (and a Windows version exists), and had a PS2 sequel called Aqua Aqua. It has a nice techno soundtrack that I normally wouldn't care for, but here I think it fits the atmosphere well, aiding its weird sense of calm tension.
Have you played Wetrix?