He is the sootopolis city gym leader.
If you mean "Is Juan the leader in Pokemon ruby?", then no. It's Wallace who's the leader. Juan is leader only in Pokemon emerald. The champion is Wallace in Emerald, but Steven is the champion is Ruby and Sapphire.
after you see groudon for the first time but only see it. i no this isn't very helpfull, but ask the question "How do i catch groudon in Pokemon ruby" or ask "Where and how to catch groudon in Pokemon ruby"
I believe you have to talk to Wallace
In the 8th gym. he is the gym leader
by fighting
new mauville after you get a key from Wallace
Pokemon ruby's version IS Pokemon ruby.
In Pokemon Ruby, Wallace is the gym leader of Sootopolis City. When the player first arrives in the city, Wallace is not at the gym. He and Steven are north of the city. They take the player to the Cave of Origin where Groudon is encountered. After this battle, Wallace can be found and battled in the Sootopolis Gym.
Go to the Elite 4, and beat them.
I don't know!Wallace appears in Ruby Sapphire and Emerald.Most likely from Emerald but there may be some elements from Ruby and Sapphire.
Wallace he was the former 8th gym leader in ruby and sapphire
Wallace is the Gym Leader of Sootopolis City so you will be able to verse him once you challenge the Gym.