Climb (Str; Armor Check Penalty)
If you don’t have a natural climb speed, you can use a move action to climb at up to one-quarter of your speed by making an appropriate Climb check. With a successful Climb check, you can advance up, down, or across a slope, a wall, or some other steep incline. A slope is considered to be any incline at an angle measuring less than 60 degrees; a wall is any incline at an angle measuring 60 degrees or more. A Climb check that fails by 4 or less means that you make no progress, and one that fails by 5 or more means that you fall from whatever height you have already attained.
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Being Attacked while Climbing:
While climbing, you can't move to avoid a blow, so you’re denied your Dexterity bonus to AC. You also can’t use a shield. Any time you take damage while climbing, make a Climb check against the DC of the slope or wall. Failure means you fall from your current height and sustain the appropriate falling damage.
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Natural Climb Speed:
A creature that has a natural climb speed moves at the noted speed while climbing. It has a +8 racial bonus on all Climb checks. The creature must succeed on a Climb check to climb any wall or slope that has a DC higher than 0, but it can choose to take 10, even if distracted or threatened. If the creature chooses an accelerated climb, it moves at double the given climb speed or its base land speed, whichever is lower, and makes a single Climb check at a –5 penalty. Creatures can’t run while climbing.
A creature that has a climb speed retains its Dexterity bonus to Armor Class while climbing, and opponents get no special bonus on their attacks against it.