In each round you have to win (be the 1st to finish) a predefined number of races from a given pool. You immediately advance to the next round after achieving the required number.
Some tracks are clearly not viable, but there are a few where improvements can be made with proper shortcuts.
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Round 1 - You have to win 1 of these races:
Kenya (3 laps), approx. time 2:02 [Viable]
England (3 laps), approx. time 1:59 [Preferable]
Chile (3 laps), approx. time 3:42
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Round 2 - You have to win 1 of these races:
Mexico (3 laps), approx. time 3:27 [May be viable with optimization]
Australia (3 laps), approx. time 3:02 [Preferable]
USA water (3 laps), approx. time 4:12
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Round 3 - You have to win 2 of these races:
Ireland (3 laps), approx. time 2:08 [Preferable]
USA land (3 laps), approx. time 4:44
Egypt (3 laps), approx. time 3:10 [Preferable]
China (3 laps), approx. time 4:01
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Round 4 - You have to win 2 of these races:
Germany (3 laps), approx. time 3:32
Arctic (3 laps), approx. time 3:42
Russia (3 laps), approx. time 2:33 [Preferable]
Japan (3 laps), approx. time 2:38 [Preferable]
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Round 5 - You have to win 2 of these races:
Italy (3 laps), approx. time 4:04 [May be viable with optimization]
Norway (3 laps), approx. time 4:07
Mars (2 laps), approx. time 3:02 [Preferable]
Spain (3 laps), approx. time 3:44 [Preferable]
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Round 6 - You have to win 3 of these races:
Venus (3 laps), approx. time 3:03 [Preferable]
India (2 laps), approx. time 4:15
France (3 laps), approx. time 3:52
Hawaii (3 laps), approx. time 3:07 [Preferable]
Scotland (3 laps), approx. time 3:03 [Preferable]
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Round 7 - You have to win this race:
Moon (4 laps), approx. time 3:55 [Mandatory]