>>20198801It's literally Fire Red with online.
Catching and battling is the same, and the story plays out as normal.
Like any MMO, there are guilds and friend lists so it's the "funner with friends" style of play., and there are sometimes events for pokemon not usually in FR.
I think it now has the typical F2P store with costumes and shortcuts, but that's mostly optional, and if I remember correctly, you can always mod the client to have different GUI and effects to make it look better, not just having HGSS.