My Rival

I don't think so. You might see him on an island, but I'm not sure.

Yes you do! After the highly annoying credits finally finish rolling you are back at professor Oak's lab about to recieve the nationaldex and your annoying rival comes in and rudely demands why Oak is favoring you all of a sudden. Then if you head to four island he strolls in the port and announces that he already has a Pokemon egg. That is the last you ever see of him (as far as I know!) Yay! XD

You can see him once in Four Island, Six Island, and maybe Five Island (I'm not so sure 'bout this one) but you will never see him again wandering outside. The only place you can see him is in the Elite Four.

He will be on one of the Sevii Islands. And of course you can always battle him again in the Elite Four.

He will be on the Sevii Islands and as Eonteam123456 has just posted " you can always go back to the Elite Four and battle him.

Yes but not to battleunless ya go backto the elite 4 then ya gotta batal him!)

There aer mixed things that are true yes you see him again once youre in prof. Oaks lab getting national pokedex you see him right as you leave the port on four island,and the last(besides elite four)that you see him about is the Pokemon center on six island which is a major clue that you should use cut on the dotted hole to get the saphire(they use him to explain that the saphire is there used to trade with other games cause he says tehre are other Pokemon we can't get hanging around here so that means trading with ruby and saphire version after aquiring the saphire and ruby for celio).

I believe you might be able to see him in his house or if you challenge him again via the Elite Four.

Hope this helps.