Liquid Tower Defense is a game for 2-9 players (you can try playing it with only 1 player, but I sure didn't get far on my own...). Everyone is on the same team, and the goal is to survive all 32 waves of creeps. There are 20 lives total, which means 20 leaks and the game is over. There are 4 races available, each with different strengths. It's important to begin building right away, as towers take some time to build. You get gold at a basic rate, as well as gold for killing creeps.
The final player (grey) gets extra gold since they're the one at the end and in a large game (9 players), they may not see much action. However, their position is important, since all creeps that don't die will travel to their area last before leaking.
Spawns travel from the top left and bottom left towards the right side where they start to meet up towards the middle and travel back again towards the left. It sounds complicated, but it's really quite simple.
This version does not have lottery towers. If you're looking for that version, head to the "Reign of Chaos" map section on this site.
Liquid tower defence is a pretty fun map, and certainly worth a try with friends. It's not extremely difficult to beat, but is rather fun and can still present a challenge.
Liquid Tower Defense v2.9 727kb
To save, right-click on the above link, and choose "Save As". Browse to your maps directory and save there (usually C:\Program Files\Warcraft III\Maps\Download).