Using the rules as written, the magi in my saga are aware that enchanting an enemy's sword is a reasonable defense against it. But this could lead to multiple enchantments being placed on the same weapon. In which case, which penetration is required? All of them?
For instance:
Magus A casts The Tricky Blade against his opponent's soldiers (grogs and their companion leader). The spell has a low penetration, to protect the magus from the swords completely.
Magus B casts The Enchanted Sword (yeah, I suck at naming) on his companion's sword. This spell has a high penetration.
So presumably, when the companion attacks Magus A, the low penetration of A's spell would be the effective one on the attack, right?
Finally, The Tricky Blade's level is 30. Unraveling the Fabric of Terram at level 20 would be sufficient to dispell it on one weapon, right?
The Tricky Blade
ReTe 30
R: Sight, D: Diameter, T: Group
Cause the target blades to tremble in their wielder's hands, causing a -1 to all attack totals. It is designed to by a high level spell cast with low penetration.
Base 2, +2 metal, +1 Diameter, +3 Sight, +2 Group
The Enchanted Sword
CrVi 10
R: Touch, D: Sun, T: Individual
Makes the sword magical for effects of wards and parma. (This was specifically designed to be used against wizards who use ReTe wards to protect against mundane weapons.)
Base 3, +1 Touch, +2 Sun