Magma Rock

The Magma Rock are a key item in Xenoblade Chronicles. It is guaranteed to be dropped by in the Lava Cave on Valak Mountain. It is needed for the Story Quest The Magma Rock and to melt the ice wall blocking the entrance to Harict Chapel, as well as three other places on Valak Mountain.

Map
The Magma Rock can be used to melt these four ice walls: