Iberian Runes are an older variant of Verditius Elder Runes.
They were used for writing in several local languages of that ancient era. Some were translated by Romans, some tongues lost and texts forever indecipherable.
Valdarius had a minor breakthrough just before the Schism War, and descendants of his lineage learn to use this script which, even more than the verditius, make them the undisputed masters of enchanted weapons.
Advantage: includes runes for Muto and Terram
Disadvantage: lacks Intellego and Mentem