Luigi Circuit has two shortcuts:
- Near the end of the straightaway, you will see a ramp. Use a mushroom to get on it and then do a trick to get another boost.
- At the end of the straightaway, there will be lots of boosts to speed you up. Go to the right of them and use a mushroom to take a shorter route and avoid the pipes. You will miss the boosts but you will already have sped up since you used a mushroom