Raiding?

In my case, mostly working with random people. I only know about 8 players, and the closest of them lives a good 5 miles from me.
Plus, I think it would be interesting to form up with players from other teams.

You guys noticed the "group code" with 3 Bulbasaurs?

I bet multiple parties can do the same "RAID". Not limited to the 20/21 players mentioned in the announcement. And if you have the same "group code", you attack together.

If there are 19 players already attacking and reaching the end, I don't think the game will just let the 20th player jump in and also claim the win. If so, there will be a new word for this action like "Raid Sniping".

I'm part of a 40+ members crew so this is gonna be fun.

You don't have to be on the same team, or am I missing something?

All 3 teams are represented in my family, and so far that hasn't been helpful... but it may soon not matter anymore.

The most popular park in the city (1 km loop trail around a lake with 15 stops but a single gym, that turns over every 10 minutes or so) should soon be the place to hang out! Everyone, complete strangers who love PoGO, gets along and it will be easy to find 20 trainers for gym raids.