Armor Class Types Cheat Sheet

AC

This represents your defense against attacks from monsters.

|AC|

This represents an AC that can only be beat by rolling a value equal to the AC on a natural die roll. Luck effects, ++’s, and other die setting effects can modify this. For |AC|’s over 20, you must be able to hit the group with the attack in order to hit the attacked target.

iAC/iiAC/iiiAC/i^NAC/etc.

This represents an infinite amount of normal AC. Rolling a 20 on your d20 to hit, sources of iTH, etc. will hit this AC. Every |AC| 20 equals iAC 1. This is similar for ||AC|| and iiAC, |||AC||| and iiiAC, etc.

||AC||

This is similar to |AC| except at ||AC|| of 2, you must be able to hit the legion with the attack in order to hit the attacked target. With ||AC|| if a target is casting a spell against you, they must roll to hit you to affect you with the spell. This type of AC ignores all die setting effects, but luck effects and ++’s still work. Every ||AC|| 20 equals iiAC 1.

|iAC|

This represents an infinite amount of |AC|. This means that you need a source of iTH and to roll a natural 20 on your d20 to hit.

|||AC|||

This is similar to ||AC|| except that your d20 to hit must use nothing else. No luck effects, ++’s, or other die setting effects will work.

|…^∞|AC|…^∞|

This represents an infinite amount of |’s of AC. This usually means you cannot be hit by attacks, spells/psi/innates (group or otherwise) unless the attacker has some way of ignoring/converting this AC type.

iⁱAC

This represents and imaginary number of iAC. Normally not seen outside of Ultraplanar beings, this AC type requires you to have an irrational/imaginary amount of iTH to beat it.

Stun AC

This represents the amount of digits of normal TH you must have to beat this AC.

(5e)AC/(5e)iAC/(5e)|AC|/etc.

This only cares about the attacker's last two digits of their TH(similar if (5e)iAC, etc.