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I'm the OT on the Thundurus, so I can give it any name you want. Also, If you already have a male with encore, that's good enough. I'm planning to only use it as a parent anyways and I can just level it up myself.
I'm on Pacific Standard Time (GMT -8). You wont be able to get endeavor on it unless both parents know the move. In any case, as long as it's male it doesn't matter. What's your time zone and availability?
Sorry, I've been chilling with my girlfriend :3 Back now though. Don't worry about trading me anything, just help me learn to RNG and I'll give it to you.
Unless my rain advancement guess is by some miracle correct, its pretty much pure luck. The only other thing that can be done is to pick a seed where timid nature appears a lot on the PIDRNG.