Wi-Fi

[Kittenbrs]

I fyour battling with someone and they send out a pokemon you need on your pokedex, will it be added?

[RoBottnik]

Near as I can tell, no. The only way to add it is if you're battling a trainer within the game itself, or you trade with someone. Battling over wifi will not fill out your 'dex, at least not from what I've seen.

[Kittenbrs]

That stinks. Thanks though

[RJOsborne]

No, unfortunately battling over wifi does not add information to the pokedex; not even as having seen it.

This is also true about people you battle within the battle tower, which is possibly more annoying.