I'd appreciate it if someone did the math on this one for me. I'm also just checking this out because I posted an evasive Garchomp moveset.
If a Garchomp with sandveil is holding brightpowder, and is in a sandstorm, then maxes his evasiveness (uses double team 6 times) what is the chance (%) of a move with 100 accuracy hitting him?
With Sandveil in the sand. 80% With both Sandveil and Brightpowder. 64% With 6 Double teams. 21%
Sandveil gives 20% Brightpowder another 20% Double-team x 6 3/9
Source: Bulbapedia