"Legend tells of a trainer that lives on the summit of Mt. Gin, one possessing knowledge beyond his years and pokemon stronger then any this land has ever seen. Some say he is waiting, waiting for the one trainer that can best him in battle and surpass his skill. Many have attempted to climb the mountain and challenge this trainer, but all have come back broken and defeated. But one day, one day there will be one who will defeat him."
This is concept art I had drawn by https://www.furaffinity.net/user/immelmann of an idea I had for if Gamefreak ever gave us a Legends game set in the Johto region. Basically it's What would it be like if a much older Red had been pulled into the past like the player. This would be a post game challenge on top of Mt. Silver like HGSS. During the main story you would hear rumors of this trainer on the mountain summit, but would be unable to go there due to a raging blizzard blocking your path up. Then during post game you would be able to clime the mountain, facing high level pokemon the whole way, until finally you would Reach the summit and face Red. He would have his old team from HGSS, but now all lvl 100 and with best possible EVs. If and when you beat him, you would be rewarded with the first words Red has spoken in the whole series, telling you how he's finally found a trainer stronger then him, before turning away from you. There could possibly be a reward, but I haven't figured that out yet. ^^;