Tumble

Characters with high tumbling skill are able to roll away from attacks during combat, positioning themselves safely at all times. Anytime the character might receive an attack of opportunity for moving past enemies, they will automatically attempt a Tumble check against a difficulty class of 15. If successful the attack is avoided. For every 5 ranks in this skill (base ranks only, not including feat-, dexterity- or item-bonuses) the character's armor class is also improved by +1.

• Ability: Dexterity

• Classes: Assassin, Bard, Monk, Harper Scout, Rogue, Shadowdancer

• Cross-Class: Yes

• Requires Training: Yes

• Check: DC 15 to avoid attack of opportunity while moving.

• Special: Wearing armor may incur a penalty to the roll.

• Use: Automatic

Notes

• Added in the expansion packs.
• Since the DC is fixed, a tumble skill of 14 is sufficient to avoid all attacks of opportunity provoked by moving through combat. However, relying on this bare minimum is not advised since a character may want heavier armor at some point (increasing the armor check penalty), and a character could be hit by skill-reducing effects (e.g., blind, curse, Curse Song, level drain).
• The spring attack feat is effectively redundant as long as a tumble skill of 14 is maintained.
• The mobility feat's usefulness is reduced—but not eliminated—by taking ranks in tumble, since some attacks of opportunity can be avoided.
• A character with a high tumble skill may want additional ranks in tumble solely for the AC bonus.
• An armor check penalty does not lower the AC bonus gained from Tumble.
• The armor class bonus from tumble is often called a "dodge bonus", but it is actually one of the uncapped other sources of AC.
• The AC from tumble is lost when flat-footed (even if the character has uncanny dodge).