you find it underwater
no you do not have to catch a relicanth to get a rayquaza
You can catch it when you use dive.
To catch relicanth use Hypnosis by Gengar and get lots of Dive Balls
You can't catch Relicanth. You have to trade from Ruby, Emerald, Sapphire or any other game that has him captured.
No only in ruby and sapphire and emerald.
Underwater near sootopolis city its rare though.
in a dive area near sootopolis city peace :)
in fire red yes in emerald no
underwater routes 124-126,but rare.
erwater cavern surrounding sootopolis city
You can see and catch Relicanth under the water just outside Sootopilis(spl?) City, in the mossy grass.
Relicanth are very rare, but you can find them on underwater routes 124 and 126.