The Drain resistance is a passive skill used to help resist the effects of magic spells in the following magic lines:
**Skill Use
**Magic resistance skills are used automatically in combat. Whenever a spell is cast on you a check is made to see how much resistance skill you have and your resistance skill is used to reduce the effects of the spell by an appropriate amount.
There are two different resistance formulas, one is used to resist damage type spells while the other is used to resist spells that have an effect over time.
EOT Formula
Effect Reduction = (RESISTANCE SKILL / 75)
This means for every 75 point in this skill the length of the spell is reduced by one round.
i.e. With 150 resistance a 3 round spell will only last one round.
Damage reduction Formula
Effect Reduction = (RESISTANCE SKILL)
This means for every 1 point in this skill the amount of damage a spell weak to this resistance deals is reduced by 1point..
i.e. With 500 resistance a 750 damage spell will do 250 damage.
Resistance skills are not trainable, they are passive skills that come from spell effects and item or mount bonuses.
It typically takes a great deal of work to get a set of armor to make you strong against specific types of magic, however as there are a dozen or more different magic types it will be impossible to become resistant to ALL types of magic.