Reduce Person

Source reduce person

You can decrease the target's size by up to two categories, to a minimum of Tiny. If the target shrinks two sizes, its weight decreases by a factor of 16 and it gains a +4 size bonus to Dexterity, a –4 size penalty to Strength, and a +2 bonus on attack rolls and to AC because of its decreased size. A Medium or Small humanoid creature whose size decreases to Tiny has a space of 2-1/2 feet and a natural reach of 0 feet.

Mythic reduce person counters and dispels mythic enlarge person.