Gloomba Grotto!
A subterranean race through the caverns below the Mushroom Kingdom, this course is a five-part track characterized by several tricky stretches of track.
Green Section: The race starts in an wide, open cavern that ends in a broad curve toward the harder parts of the track. The section grants a +1 bonus to power slides.
Red Section: Though the track is starting to narrow here, there is one broad area that has a short line of item boxes on either side. Drivers who want an item must choose either Right or Left- if everyone goes to one side, you may have trouble finding an available item box. At the end of the section is a very sharp right turn that requires a +1 Racing Check to navigate.
Blue Section: The cavern opens back up here, as the track takes a loop around a deep lake. The main track section is another broad curve that works well for power sliding (+1). An alternative shortcut is available, requiring racers to make a jump over the lake. The jump requires a +1 Racing Check to successfully navigate- having Mushroom assistance on the jump increases the bonus on the check to +3. Fail the jump, and you land in the lake and Fall Back.
Purple Section: Stalagtites and stalagmites litter this narrow, rocky section of track. They constitute a +1 Hazard Check. Failure results in spinning out and losing two momentum. There is a dash panel at the start that is optional- hitting it gains you one momentum, but results in the hazard checks being made with no bonus!
Orange Section: As you emerge from the narrow Purple Section, the cavern opens back up to a mostly straight section as a home stretch. There is a broad line of item boxes (+1 to hit) and dash panels to give one momentum and a fast finish!
I like it! Purple is a particularly nice little choice for the drivers. If I may ask, what specific advantage were you thinking of for the shortcut in Blue- automatic Pull Ahead regardless of intervening drivers? Either that or a substantial Momentum boost is in order- think I might make the Jump a little bit trickier in either event. The only thing I might change is Item Box placement; the Item Boxes in Orange won't really count on the last lap. I may push those back to Purple, with the caveat that the Dash Panel Path bypasses them. Or maybe you just don't get a bonus on the Items either, same as the Hazard.
I had +2 momentum for making the jump written down in my notes, but apparently it got lost in translation. I was considering an item box at the top that's guaranteed to be hit by the first driver across the jump each turn as well if that wasn't enough. Also, failing the sharp curve check in Red is a small penalty- probably -1 momentum from bouncing off walls.
I tried to include a few interesting choices for drivers, and I agree Purple was the best. It's inspired from actual gameplay, as well; there are a few courses where dash panels are awfully risky to take. Item box placement was hard on this one- originally there was a small line in Purple as well that got nixed in the final design. Purple's the logical spot, but I don't think they mix well with the design. Ones in Orange wouldn't be useful in the final lap, sure, but if it's a three lap race I don't see that being a huge issue. Two lap race may be- but if it's two laps, there's room for another section between Purple and Orange which the item boxes would be moved to.
Another possibility would be swapping the Orange and Purple segment, but that interferes with the grand design of the track- a long hard middle with an easier start/finish.