Place 2: Ezekyle Abaddon, the Despoiler
As the first character on this list, Abaddon is the champion devoted not to a single god but to all gods of chaos – or the “Undivided Chaos.” Abaddon is the current leader of the Black Legion and the main antagonist in Warhammer 40,000, seeking to eradicate the Imperium and most of the galaxy with his Black Crusade.
The current Warmaster is the direct successor of Horus, the traitor, through whom the Emperor was first bound to his golden throne. Abaddon, on the other hand, is responsible for tearing the entire galaxy apart.
During his 13th Crusade, Abaddon destroyed the world Cadia and thereby – knowingly or not – caused a rift in reality. The “Great Rift” now divides the galaxy. It is difficult to impossible to cross, and it blocks any communication via astropathic means.
Although he is not a primarch himself, his power exceeds that of daemon primarchs. Even though he would likely fall in direct duel against most of them, he poses a greater threat.
Unlike the other leaders, Abaddon is still “human” (as human as a Space Marine can be) and can therefore exist permanently in real space outside the Warp. This makes him an acute danger to the Imperium – and to all others. Moreover, he carries the blessings of each of the four chaos gods, from the weakest to the strongest: All chaos gods in Warhammer 40,000 ranked – Who is the most powerful?