not only can you not capture other peoples Pokemon, you will throw away a poke ball for nothing!you can only trade for other peoples Pokemon
do you mean catch other peoples' pokemon? you can't.... not even with with a masterball!!!!
You can't catch them, but you can certainly trade them from other games.
nope
You can use a Action Reply codes to catch other trainers pokemon.
You can usually catch others Pokemon by using a Master Ball(does not always work)
The only way to catch Celebi in Pokemon FireRed Version was to get the special Pokemon from a event. The only other way would be to cheat using an action replay device with a code.
You can't, it's impossible!!
impossible unless if you trade it form Pokemon leafgreen or other related Pokemon games (except DS Pokemon games) . in other words it is a Pokemon version exclusive Pokemon like growlithe (firered) and vulpix (leafgreen)
Riolu and other 4th generation Pokemon don't exist in previous generation Pokemon games this means it can't be obtained in firered or any game before that.
YOU CAN'T CATCH OTHER PEOPLES POKÉMON. it's against the pokélaw:)
You can't if you try to its one pokeball wasted.
no it requires an action replay or any other cheating device to catch other people's Pokemon but i wouldn't recommend it because it can destroy your game