Badwater Basin is a Payload map released with the Heavy update in Team Fortress 2. This map focuses on differing vertical heights. Instead of having three separate stages like Goldrush, it is compacted into a single stage, pushing through many checkpoints to the final point, and rewarding the player with a spectacular explosion. It is more oriented towards open play as it has fewer choke points than Goldrush. Some players believe it is slightly biased toward the defending team, but there are many flanks which help the push on the final point.
The first point consists of a push from the Blu spawn room, through a narrow choked tunnel, to a small gap between the centre ridge and a building. From here the cart much be pushed to the second point between 2 large buildings, with the defending team spawning nearby this may seem a small push but is made quit difficult by its setup. Once Blu pushed to the second point the Red's spawn has one of its doors blocked making them use the long route to get to the cart. Blu mush then continue pushing down a small hill under a building to the 3rd pont. Once this is capped they spawn at the 2nd point rather than the first. Then begins Blu's final push to the last point which is arguably the most difficult. This requires Blu to push the cart around a narrow choked corner and down the a basin with many spots for Sentry's and sniper's among other things. After the Bomb is pushed to the final point Blu is declared the winner and bomb drops into the basin causing a large explosion.
This is the second payload type map in Team Fortress 2, the first being Goldrush.