Do we want this thing? Well, everyone likes a dex entry, and you need mega candy for that. For PvE I guess you can use it to boost same type attackers, but it’s not something you’re going to miss too much. For PvP? It has some use in great league, especially in special cups. There is definitely a spot in ultra league, you will want XL for that. I guess you will be grinding for it you crazy Go Battler you.
Top counters? Do you have fighters? I’m going to ask that every other raid boss, so get them anyway you can. Some community day mons show up here, so don’t skip those either. Maybe that Crab will finally get put in the game!
Go to the official counters page for a complete list including Shadows and Megas to see how your Pokemon perform.