The Abyssal Knights are an alliance between the Void Knights and the Temple Knights. The Abyssal Knights' current commander is Kenton Decarte. The Abyssal Knights were formed to protect Gielinor from the deadly creatures that pour from the Abyss.
The Abyssal Knights share many similarities with the Brotherhood of the Horadrim from the Diablo video game series. They are both orders formed from differing groups, both are dedicated to guarding against an external threat, and they have equipment of similar design. Additionally, the leader of the Abyssal Knights Kenton Decarte is based upon Deckard Cain, a member of the Brotherhood of the Horadrim descended from the Brotherhood's leader.