Smokey's Course is the fourth boss stage in Diddy Kong Racing and Diddy Kong Racing DS. It is an aerial race against Smokey, which features the player racing in a Plane. Smokey's Course is set in a grassy valley, with a series of cavern tunnels and a few windmills. Like the previous boss race, Bubbler's Course, this stage is done in three laps.
If the player manages to win against Smokey, they can re-challenge him once they complete every Silver Coin Challenge and have all 37 Golden Balloons. On his second challenge, Smokey spits fireballs at the racers, trying to attack them. Because of the many tight spaces and obstacles around the stage, avoiding them can be quite a challenge for some racers.
The beginning of the stage is set on a large field leading into one of these tunnels. Inside of the tunnels, there are several poles that can easily get in a racer's way. A few Item Balloons are also present in here to attack Smokey. The other end of this long tunnel is in another small field. A large windmill is in the center of this field, containing a blue Item Balloon inside of it. The entrance to the next tunnel is to the left of this. The tunnel is rather short, and it leads back onto an open field. The main obstacle in this open is area the trees, which can slow down players is run into. Another tunnel can be found at the end of this field. Once the player enters, they should find some more poles in their way, as well as a few more Item Balloons. Outside of this tunnel is yet another field filled with trees. The trees must be avoided at all cost to defeat Smokey. At the end of the field is one last small tunnel. Going through this empty tunnel, players can find the finish line just ahead.