Although not as big as the mighty Block Fort, Urchin Underpass is still one of the bigger maps. Huge stone pillars on the corners of the arena hold up a roof made out of glass, and around the field are huge rectangular holes. A few trees dot the place, and Urchin Underpass seems to have undergone an ink firefight as huge splotches of green and purple ink dot the place.
Relevant to stages like Pipe Plaza and/or Thwomp Desert, Urchin Underpass is kind of confusing. In the center is a large, rectangular area with a few ramps where racers can meet and toss all the Shells they want. But branching off from this lobby are 6 different paths, 3 green and 3 purple, dividing it into 2 "factions" (not including center). Each side is the same, but flipped upside down, and of course different colors. The three paths meet up to a sort of camp which is two story and has all the Boost Pads and ramps one could want.
- This is the first Battle Stage to be based off of a non-Mario series location.
- Urchin Underpass is also the first Splatoon course in the Mario Kart series.
- Five Battle Modes will be playable on Urchin Underpass, including Balloon Battle, Bob-omb Blast, and three other currently named modes.