|Rise of the Dead||Lvl 10||Increases Abaddon's DPS by 125%.||Abaddon can raise the corpses of the fallen, to fight by your side.||3.200e15|
|Curse of the Dark God||Lvl 25||Increases Abaddon's DPS by 125%.||"To call this a 'Curse' is a misnomer, mortal. This power is a blessing."||8.000e15|
|Epidemic Evil||Lvl 50||Increases Abaddon's DPS by 125%.||"The powers of darkness breed more powers," he says. Abaddon is kind of scary.||3.200e16|
|The Dark Ritual||Lvl 75||Unlocks the The Dark Ritual skill.||The ground beneath Abaddon glows with runes. He beckons for you to help him with his final ritual.||2.560e17|
|Skill Name||Icon||Description||Hotkey||Base Cooldown|
|The Dark Ritual||Multiply your current DPS by 1.05 for the duration of your world. Stacks up to 20 times per ascension.||6||8 hrs|
- Abaddon is the name of a place of destruction in the Hebrew bible, and as the name of the "angel of the abyss" in the New Testament.
- Abaddon's Dark Ritual skill may be inspired by a curse technique used by the character Hidan from the Naruto series.
- Abaddon is mentioned in Hero upgrades for Ma Zhu and Amenhotep:
- Ma Zhu's upgrade Ancient Wrath: "I fear you may not be balancing the powers of the Gods," Ma Zhu tells you, hinting at this upgrade. "Abaddon is a dangerous one".
- Amenhotep's Genesis Upgrade: "Foolish Mortal! You have let Abaddon grow too powerful," He scolds you. "We must undo what has been done! It will take time. Do not let Abaddon know"
- The Ancient Morgulis's description shows Abaddon speaking to the player about death: Approaching the monument, you begin to feel as if killing monsters is a natural thing in life. It is as necessary as breathing, and eating. A voice startles you from behind. "Death is good" he says. You turn around-it was Abaddon. He was following you. "Their death brings you happiness and gold. It feels good, does it not?"
- The Ancient Kumawakamaru's description mentions Abaddon as well: A darkness radiates from the monument, causing many things to become difficult to see. You catch a brief glimpse of movement nearby... Was that Abaddon? Upgrading this ancient will allow you to sneak past monsters when exploring.