>>53141842>Viridian Forest = goneStill there.
>Mt. Moon = see my next postStill there, but it was barely a "dungeon" in RBY anyway. Also adds a new area where you can get a moon stone once a week.
>SS Anne = goneNot a dungeon. It's literally like 3 hallways and a bunch of empty rooms. Also, there's a new SS ship that sails twice a week.
>Power Plant = goneNarrative reason explains it, it's been reclaimed and reactivated.
>Rock Tunnel = slightly smallerThank god, the one in RBY is pure aids to go through.
>Rocket Hideout = goneWhich makes sense considering by this point team rocket has been completely BTFO'd.
>Pokemon Tower = goneNarrative explanation, it's been torn down and replaced with a radio tower.
>Safari Zone = goneNot a dungeon, and there's an infinitely superior one in HGSS (not that safari zones are good anyway, they're obnoxious and shit and good riddance in gen 2)
>Silph Co = goneNo reason for it to be explorable in gen 2.
>Seafoam Islands = goneTurned into the gym, and in HGSS they've been added back in. Also fuck the seafoam islands, they suck.
>Pokemon Mansion = goneNarrative reason, ALL of cinnabar but the pokemon center is gone because a volcano went off. It was also literally only there to make getting the gym key a pain in the ass, so good riddance.
>Victory Road = slightly smallerCounterpoint, there's a far longer route to get there plus on top of that mount silver exists and is connected to the league.
>Cerulean Cave = goneAdded back in HGSS, but there's a narrative reason in GSC it wasnt' there, it caved in presumably when Red went after mewtwo. That's why you can find the berserker gene nearby.