Mario Kart is off to a roaring start.

The mobile version of Nintendo’s popular racing game has already been downloaded over 20 million times, and has generated over US$1 million.

The huge number of downloads for the Mario Kart Tour, which covers both Apple App and Google Play stores, is part of the app tracking statistics that Sensor Tower put together. To date, it is the best performing mobile game for the willy plumber.

Even while it managed to record US$1 million in user spending, Sensor Tower believes the game will still experience a slower start for spending. This is mostly due to how DeNA — the game’s publisher and co-developer — wants to experiment with season passes. This includes trying out user purchase bundles that come free subscription offers.

Sensor Tower’s current data shows that many users picked the US$3.99 Gold Pass — a bundle that comes with 14 days of free-trial access to Gold Challenges, Gold Gifts, and the 200cc engine. Once the try-out period ends, some of these bonus content will be removed, like the powered-up engine. Rewards that gamers earned from these limited-run events will not be taken away, however.

While Mario Kart Tour is still new, Sensor Tower also added that it needed to capture and analyze more data, so as to get a better understanding of the game’s monetization model. It is, after all, a mix of premium and free-to-pay content.

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