User blog comment:050294/Back (AGAIN)/@comment-050294-20100321050005

You seriously don't know? Crystal was the sister version to the original Gameboy Color Gold and Silver. It had an altered storyline, the first female playable character, and the first animated sprites. HeartGold is basically Old Gold game + New features/Graphics/4th gen Pokemon + Crystal elements and storyline while SoulSilver was the same, except it was Silver's remake instead of Gold's.

Tada.