Jhulae said:
But wait. The fact is that, with cleave, no matter how 'careful' Target A is (even avoiding AoOs and such), Target A can get cleaved whether or not whether the Cleaver is making a 'normal' attack or attacking on an AoO, as long as Target A is within cleave range when the Cleaver drops someone.
Regardless of whether it's on an AoO or a regular turn, a cleave is going to happen regardless of whether the Cleavee wants it to happen or has been 'super careful' or whatnot.
So, what's the big deal as to whether it happens on an AoO or regular attack? I'm confused by this point.
Let's consider two 4th-level fighters, A and C. For a start, assume C has Cleave.
Situation 1
In a normal round of combat, A gets one attack roll against C and C gets one attack roll against A. If A doesn't do anything to provoke an AOO, that one attack roll against A is all that C gets in one round of combat.
Now, we introduce a weak opponent B, who is an ally of A fighting against C.
Situation 2
If C attacks B, drops him and Cleaves into A, C still only gets one attack roll against A in that round. C's Cleave feat effectively allowed him to attack both A and B, but C still doesn't get more than one attack roll against A in a round of combat.
Situation 3
Now, let's say that instead of attacking B, C attacked A instead. On B's turn, he does something that provokes an AOO from C (disarm, sunder, whatever). C takes his AOO against B, and by the rules, he is allowed to Cleave into A. Now, C has made two attack rolls against A in a single round of combat (one regular attack, and one Cleave off an AOO). A is worse off under this scenario than when he was fighting C alone (Situation 1 - one normal attack) or when C Cleaved A on his turn (Situation 2 - one Cleave off a normal attack).
Some people are OK with this. They feel that it is "right" that A is made to "pay" for B's mistake, or that B's death "distracted" A and made him drop his defences, effectively subjecting him to an AOO even though he did nothing to provoke one.
Situation 4
This example is slightly more extreme. Assume that C also has Dexterity 18, Combat Reflexes and Great Cleave. In addition to B, A has four other weak allies: B1, B2, B3, and B4, who also provoke AOOs from C. For every person that C drops with an AOO, he can make an additional attack roll against A with Great Cleave. C could potentially make six attack rolls against A in one round of combat.
Of course, you can choose to see this as a feature. C needs high ability scores, four feats (including the prerequisites) and DM approval (or incompetence) to pull this off. However, I choose to see this as a bug because it seems to me that disadvantage suffered by A is out of proportion to the mistakes made by his allies.
Theoretically, if you were facing an opponent and the party Wizard summons 3 wimpy things to help attack it, when the opponent attacks and kills each summon, gaining a cleave on you, how is that any different as to whether it does the same during an AoO?
If the 3 wimpy things weren't there, the opponent could have attacked me three times in the round (Situation 1). If the opponent attacked the 3 wimpy things on his turn and Cleaved into me, I still got attacked no more than three times (Situation 2). I'm no worse off than Situation 1. If the opponent attacked me three times on his turn, and the 3 wimpy things did something to provoke AOOs from the opponent, and the opponent Cleaved into me three more times (Situation 3/4), I would have been attacked a total of six times in the round, as if I had provoked three AOOs from the opponent. If I actually had done nothing in the round to provoke any AOOs, I think I would be rather upset.