Well you see,I've finished the main story in Emerald and so I went to hunt for Groudon and Kyogre...
The thing is that I accidentally knocked them out when I'm fighting them.
Can I meet them again?
Nope. The beating E4 thing was introduced only in Platinum.Sorry. You have to restart you're game Hope I helped! -demat
Many will disappear forever if your battle ends for any reason other than victory by capture. That means if you knock out a legendary Pokémon, or it knocks you out, the Pokémon might disappear forever. That also applies if you run away from the enemy Pokémon. In short, that means all battles against legendaries are one-time-only final battles.
Sorry, no. Source
