If you're talking about the one by Ryan Jentzsch, you can replace lines 96-105 with: // Sanity check
if (smash)
{
// Send the critical result as a formatted string in chat
sendChat('Critical Hit', "/w gm "+ rolled.toString() + "% <b>" + smash.result + "</b><br><i><b>Slash: </b>" + smash.slash + '</i><br><i><b>Blunt: </b>' + smash.blunt + '</i><br><i><b>Pierce: </b>' + smash.pierce + '</i>');
}
else
{
sendChat('Critical Hit', '/w gm Invalid % roll given, or something went wrong. GM makes something up.');
}