When I was little was very dumb, I had no clue that I could soft reset when I made a legendary Pokemon faint, I thought that was it.
So to the point, I only caught one of the legends in the Lake Trio (Pokemon Diamond) and only one of the... Lion Trio. (Pokemon HeartGold) Currently, I'm trying to make my games an "un-fail" and relocate the legendary Pokemon and catch them. Since roaming legendary Pokemon aren't always in the same spot, I thought that you probably wouldn't be able to rebattle them, but I'm not quite sure.
So, can you rebattle roaming legendary Pokemon?