Riptide GP2
29 Achievements
85,000 XP
Google Play
Stunt Expert
Get 1500 points in a Freestyle event
2,000 XP
1.53%
How to unlock the Stunt Expert achievement in Riptide GP2 - Definitive Guide
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This will likely be earned during the Shoot the Loop Event in the 5th Cup, Waverider, as the target is 1500 points. While the same strategies can be used as in 
Stunt Master, you likely won't have the Tier 10 Tricks available when you first reach this Event.
I have recorded my run, using mostly Tier 5 Tricks. Note that you do get fewer points for repeats, but there are so many jumps on this Event that you should still clear the target.
Barad, KillerBEA
You will need to do this in order to get "Champion" and "Tricky Racer." See "Stunt Master" for more details.