Yes, to deal nonlethal damage with a regular weapon, you just take -4 to your attack roll.<br/><br/>But what we really want Muriel to do right now is to use her Order of the Penitent ability Expert Captor:<br/><br/><div class="quoteheader"><div class="topslice_quote">Quote</div></div><blockquote class="bbc_standard_quote">At 2nd level, as long as he has rope, the cavalier can tie up a grappled opponent, even if the opponent is not pinned, otherwise restrained, or unconscious, and he does not take the usual –10 penalty on his combat maneuver check to do so. When determining the DC to escape bonds secured by the cavalier, the cavalier’s Combat Maneuver Bonus increases by 1/2 his cavalier level.</blockquote><div class="quotefooter"><div class="botslice_quote"></div></div><br/>Punching the wyvern into unconsciousness is a perfectly reasonable strategy, but we really want him restrained so Grimaruk can work his influence on him. Grimaruk has done the first hard part by getting him grappled, and Muriel has the perfect ability to finish the job.<br/><br/>And, for reference, since the rules are scattered around a bit, here is how tying people up works:<br/><br/><div class="quoteheader"><div class="topslice_quote">Quote</div></div><blockquote class="bbc_standard_quote">If you have your target pinned, otherwise restrained, or unconscious, you can use rope to tie him up. This works like a pin effect, but the DC to escape the bonds is equal to 20 + your Combat Maneuver Bonus (instead of your CMD). The ropes do not need to make a check every round to maintain the pin. If you are grappling the target, you can attempt to tie him up in ropes, but doing so requires a combat maneuver check at a –10 penalty. If the DC to escape from these bindings is higher than 20 + the target’s CMB, the target cannot escape from the bonds, even with a natural 20 on the check.</blockquote><div class="quotefooter"><div class="botslice_quote"></div></div>