(v5.53)

Petrify attackers always works, unless you are being attacked by something in any of the 3 squares behind you. There, it is a mere 25% to work.

It is a regular MR check, but pen boost items do not work. The value of the petrify attackers ability is used as the base pen roll. Negative values will not function at all here. This is considered an Earth effect, the attacker's Earth path will reduce the penetration roll but higher defender Earth paths will do nothing.

Petrification then proceeds as normal, lasting for 2250-4500 ticks, and then hitting with a MRN for 999 AN damage. This is considered to have no source (no blood vengeance or damage reversal applies, nor does it add to kill stat). As with above, this is considered to be an Earth effect for the purposes of petrified creature's MR check, and the "attacker" is always considered to have a penetration bonus of 2.

This is why it usually appears as 13 + DRN vs MR + DRN, in the case of creatures without earth paths.