Jdvn1 said:
No, they're standard actions. They don't take the place of an attack action.
No, they're not standard actions. They do take the place of a melee attack.
Check here:
http://www.wizards.com/d20/files/v35/CombatI.rtf
Do search on the word "Grapple," and pick the second occurence.
You'll notice that Grapple, Disarm, and Trip an Opponent all have the footnote 7, which states:
SRD said:
These attack forms substitute for a melee attack, not an action. As melee attacks, they can be used once in an attack or charge action, one or more times in a full attack action, or even as an attack of opportunity.
EDIT:
So, back to the original poster's question. Can you Disarm, Trip, or Grapple on a Cleave attempt when the original attack was made with an unarmed strike?
SRD said:
As a melee attack, you may attempt to disarm your opponent. If you do so with a weapon, you knock the opponent’s weapon out of his hands and to the ground. If you attempt the disarm while unarmed, you end up with the weapon in your hand.
Disarm = Yes, absolutely
SRD said:
Tripping with a Weapon: Some weapons can be used to make trip attacks. In this case, you make a melee touch attack with the weapon instead of an unarmed melee touch attack, and you don’t provoke an attack of opportunity.
SRD said:
Kama: ... You can use a kama to make trip attacks ...
Strike, Unarmed: ...
Scythe: A scythe can be used to make trip attacks ...
Trip = No, not strictly by RAW, because the Unarmed Strike is not a weapon which can be used to make trip attacks. You could both Trip and Disarm on a Cleave attempt if you were using a kama, however.
SRD said:
Step 2: Grab. You make a melee touch attack to grab the target.
Grapple = No; Grappling does not use any weapon, and therefore cannot be Cleaved to from an Unarmed Strike.
However, should you successfully begin a grapple with a creature and, when you do your unarmed damage to it, knock it down, you might gain a Cleave attempt with a Grapple. I'll leave deciding this as an exercise for our readers.
