Legendary raids are supposed to be Pokemon GO's toughest battles, with promotional materials often showing large groups of people fighting a single monster. Turns out, it's possible to down a legendary with just two people.
Image source: Wikia
Player boushinshi uploaded a battle to YouTube showcasing this legendary feat:
You'll note that the whole thing was done with fan-favourite counter-pick Golem, with levels in the 30s, CP in the high 2000s, and likely with high IVs to boot. In this case, Golem's rock/ground-type resists Moltres' primary attacks, something that certainly helps when trying to duo a mighty monster. The players have to go through a small army of Golem to defeat Moltres, and by the end, there are only seconds left on the timer. Boushinshi just baaaaarely pulls it off.
Fans predicted this would be possible a while back, but seeing it in action is something else. To think throwing rocks at legendaries over and over again would be this effective!