SB is the shortened name for Spell Breaker. This is an Elite Skill part
of the Divine Favor category for the Monk. Spell Breaker is an enchantment
that renders all spell casters useless. Whenever you have Spell Breaker and
a monster or player tries to cast a spell on you, that spell will fail and
will not be casted. Spell Breaker is one of the skills that is popular for
dealing with Dying Nightmares in the UW, who will try to strip all the
Enchantments on a 55 Monk by using Rend Enchantments.

EXAMPLE: LF Monk with SB for 2-man UW Farming!