> That's not Red on Mt. Silver in HGSS, it's Leaf.
>Red and Leaf look the same, and they may even be siblings. They're gender bent versions of each other, unlike other protagonists (even Dawn and Lucas look quite different). Just put Red's hat on Leaf, with most of her hair in it, and put on Red's clothing and they're identical twins. Red is also completely silent, which goes against the hints to his personality pre-timeskip.
> "Red" does not exist.
>Inspired by the above. He's a persona of Leaf. Leaf goes into drag, probably since there are few female trainers at that time or such. Why doesn't Blue know? Either he does (maybe that's related to his Jerk Ass behavior toward him/her), or he thought Leaf was a boy for their entire friendship.. Or she made an excuse about her going away or something, and her non-existant brother coming over.
My life was a lie
>You killed your rival's Raticate on the S.S. Anne.
>In the game, you encounter and battle your rival in Lavender Town. He asks something along the lines of whether you're there because one of your Pokemon has died. When you battle him, you find that he no longer has the Raticate he had possessed in earlier battles. Before this battle, you had fought your rival on the S.S. Anne, and his Raticate, having taken severe damage, was unable to make it to a Pokemon center after the battle due to the crowding on the ship. The real reason your rival is in Lavender Town, in the Pokemon Tower, is to lay down his dead Pokemon.
I remember reading that theory here on /vp/. Shame on you, tv tropes.