Hey /vp/, I have a stupid question. Not new to Pokemon, but new to keeping up with stats and in-depth stuff.

Has GameFreak ever outright changed a Pokemon's stats before? Excluding things like new forms and megas, have they ever actually just outright buffed Pokemon that needed it by upping/tweaking stats? I see a lot of people on /vp/ saying buffs they'd like to see certain Pokemon to get, but is there any actual chance of such things happening, or is it just wishful thinking? Especially mid-gen?