I did as well, but didn't get Drought, so I didn't bother resetting and beating the thing again.
I lead with a Glameow, used Fake Out, had to rely on it missing a move, or using automotize, which it did. Then, I hit with hyponosis.
Then I switched to (previous evo of greninja) and water pulse confused it, then switched to haryama and proceeded to vital throw.
It did require like 3 times of it hitting itself, but still.