Resistance
Resistance is a secondary skill that increases the magic resistance of hero's troops. Warlocks, Witches and Wizards cannot learn Resistance.
Heroes with Resistance as a starting skill:
Ajit the Overlord - Basic Resistance
Bron the Beastmaster - Basic Resistance
Clancy the Ranger - Basic Resistance
Fafner the Alchemist - Basic Resistance
Thorgrim the Ranger - Advanced Resistance
Ignatius the Demoniac - Basic Resistance
Krellion the Barbarian - Basic Resistance
Saurug the Battle Mage - Basic Resistance
Straker the Death Knight - Basic Resistance
Ufretin the Ranger - Basic Resistance
Heroes with a Resistance specialty:
The following heroes receive a 5% per level bonus to their Resistance skill.
Discussion
It is a common misconception that Garniture of Interference, Surcoat of Counterpoise or Boots of Polarity would increase the resistance secondary skill in a similar way that for example Bow of Elven Cherrywood increases Archery skill. However, this is not the case. The "resistance artifacts" increase the magic resistance of creatures in a similar way Resistance secondary skill does. Basically this means, that wearing any of those artifacts gives the magic resistance bonus with or without the resistance skill – unlike with archery artifacts and Archery skill.
While resistance may not be reliable, it can turn the tide of battle against a magic user when it takes effect.