Armor Class

See also: Spell Armor Class

Armor Class, or AC, directly translates into a % of potential damage reduction on hits. For example, 1500 AC is ~80% potential reduction. Then, a fourth of that is turned into certain reduction (meaning at 1500 AC you always reduce hits by at least 20%) and the rest is randomized for the true reduction number for a single hit (so reduction is anywhere from 20-80%, and on average 50%, at 1500 AC).

There are three softcaps of AC, and they do not vary based on class. One at 100 (each point before 100 makes a much bigger difference, so that AC on lower levels is more useful), another at 250 (each point before 250 makes a much bigger difference, so that AC on lower levels is more useful), and finally at 500 (each point before 500 makes a bigger difference, same reason as above). After 500 all AC is the same.