Well, y'know there's an attack stat' and a special attack stat'? Whether a move draws from the attack or special attack is determined by whether or not that move is physical. In generation 4 and higher, each move had its own classification as special or physical. In generation 3 and below, however, it depended on the type. So even if I used vine whip, which is a grass type and seems like it would be physical, it would actually depend on the special attack stat'.



Solarbeam, being a special move, and remaining a special move even when you have him in a generation 4 game, isn't particularly effective on Groudon, since he has an average special attack stat', and Kyogre has a monstrous special defence.