Question

Can I catch Groudon if I've killed it in the origin cave?

Comments

You should be able to catch it after defeating the Pokemon league, but I don't play ORAS, so I don't know the full details (level, location, etc.)

Answer 1

You are able to catch it after beating the Elite Four. It will appear in the Cave of Origin. At Lv. 70, if I remember correctly. I answered an identical question here.