Not sure if anyone's discovered this before...but you can manipulate the mix rotation battles (haven't tried the other battles yet) to get the AI to pick a certain Pokemon.
I first discovered this when I jokingly took my lv 100 EV trained virizion, newly hatched geodude, UT lv 35 reversal mountain volcarona and newly hatched wurmple into the mix rotation PWT.
In the first matchup, the NPC (think it was Clay) picked my geodude and I thought 'phew, thank goodness he took an UT pokemon, if virizion got picked there's no way I'd win.'
In my second and third matchup, the AI took my volcarona twice.
When I tried again in the tournament with virizion, budew, volcarona and wurmple, the AI picked Volarona every single time. I'm starting to think that the game picks a pokemon of yours that has the best type advantage against your entire team, regardless of their stats.
This means that you can essentially trick the AI into receiving a useless Pokemon (or at least a weak, UT pokemon). It IS kind of risky because if you take a team of three that's weak to another type and your opponent happens to have that type, you may have a bad time. But assuming your fourth 'useless' pokemon is taught a rubbish movepool and is completely untrained, you're basically fighting 4 to 3, which I guess might be beneficial. I think I may make my team virizion, volacrona, heracross and pidgeotto, and teach pidgeotto some useless moves.
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