When Ofto’s irresistible dance is placed upon a creature, the spell causes the recipient to begin dancing, feet shuffling and tapping. This dance makes it impossible for the victim to do anything other than caper and prance, this cavorting lowering the armor class of the creature by -4, making saving throws impossible, and negating any consideration of a shield. Note that the creature must be touched — possibly as if melee combat were taking place and the spell caster were striking to do damage.