The 1st condition(Move Toward: Arena Hex) should always be attempted autonomously of the other conditions unless two equal options present themselves. In that case, you look at the 2nd condition along with the first.
Ariq is moving toward an Arena Hex, as opposed to Zipa and Zaque (El Dorado), who won't move if they cannot improve their position (stated in their Move rules).
Ariq and Kublai don't want to just sit idle and will make an attempt to move toward an available Arena hex even if its more than a single move away.
If Ariq is already on an Arena Hex, he will stay put, unless he has 2 equal options that further fill his Move directive, if he can stay on a stone AND end up next to an opposing unit, he will do so.