Attack bonus (AB) is one of the two most important statistics for a character engaged in combat, with the other being armor class (AC). With an insufficient AB, a character will hit only 1 time in 20, while an exceptional AB could allow a character to hit 19 times in 20. (However, being at the latter extreme is rare if fighting level-suitable opponents.) What constitutes "insufficient" and "exceptional" in this context depends on the opponent being fought; an AB that is 20 less than the opponent's AC (or lower) is insufficient, while and AB that is 2 less than the opponent's AC (or higher) is exceptional. Furthermore, the term "insufficient" should not be taken too harshly, as a character with a quite adequate attack bonus and multiple attacks per round might find the later attacks in a ro