Wild West Weaver is a race course that's new to Mario Kart: Mega Mash-Up. It appears in the Mushroom Cup.
The course is set in a canyon in the Wild West. You start off by racing into the canyon which weaves left and right several times. Along the canyon are many goodies, such as item boxes and Boost Pads however there are also bad things and delays, like the thick mud and Piranha Plants. After weaving through the canyon, you go through a turn and drive back towards the start line in a straight line next to the canyon, taking a turn to reenter the canyon.
- Piranha Plant - There are multiple Piranha Plants positioned at various places through the canyon section of the map. They will lean towards oncoming racers and coming into contact with them will cause the driver to spin out.