Quote Originally Posted by Rengori
Where would the other meteor be?

errrr.... did you visit the one where Walz tower sunk?

I think the ones you have been to are:
Tycoon castle (1st meteor no boss)
Karnak (3rd meteor Titan)
And Earth crystal/ Ronka ruins (4th meteor Kimabrain)

So yup that leaves Walz tower and Pyuroboros