Unown could be part of many biomes, or none at all, but either way it's incredibly rare to find. ... Unless you can catch one at an event, catching Unown is a case of patience of and a healthy dose of luck - something seasoned Pokémon Go players should be used to by now!

Should I catch all the Unown?

While catching all the Unown forms A-Z doesn't have many advantages, it's still a great way to finish off your Pokémon game. You can show an Unown to a boy in Solaceon Town to get capsule seals, or just catch all of them to get Unown forms ! and ? and to see the Ruin Maniac finish digging the tunnel.

What is the point of Unown?

Other than some plot points, such as in the Unown Movie, Unown serves no purpose whatsoever. In DPPt, there's a boy who will give you some alphabet seals if you show him an Unown, and he will give the corresponding letter seal to the Unown letter you show him. Unown is the most pitiful Pokemon in the metagame.