Size

Some polymorph spells allow you to design a polymorph form of a specific size. If you change the target’s size, it gains the space and reach of the new size. Decide if the new form is tall or long and then use the space and reach rules from Table 8-1: Creature Size. If you try to polymorph the target into a size that the physical space it’s in can’t accommodate, the spell begins to take hold but then fails. You should also select a weight within the range indicated for that size on that table.

A target of a polymorph spell gains a minor bonus based on the size its new form provides, regardless of the target’s original size. Table 1 below shows these bonuses, which are enhancement bonuses to ability checks and skill checks based on the indicated ability score.