Icon of Sin (Doom Eternal)

The Icon of Sin is a new boss in Doom Eternal, based on the boss of the same name in Doom 2, as well as the game’s final antagonist. The Icon of Sin was originally created using the heart of the Betrayer's son, as Hell's twisted way of honoring its bargain to return him to life.

It previously appeared as an Easter Egg.

Codex Entry
"As it is written in the prophecies of ancient Sentinel scripture, the Titans - towering elder demons of the infernal age - would return, unearthed from their immortal slumber. The Titans are believed to be harbingers of the end times, primordial forces of chaos and destruction. Born from the tortured spirit of the Betrayer's son, it was by Hell's unholy design that the Icon of Sin was given flesh. The fearsome Titan, forged from the essence of mortal suffering, once bore a human soul - a soul now transmogrified and entombed within the still beating heart of its former self. The Betrayer, seeking to free his son from eternal torment within the dpeths of Hell, made an agreement - a pact sealed by the black fates of darkness - that promised to grant his son the chance to return from death. The son would live again, but not as human - in Hell's endless cruelty, the son was damned to become the Icon, an inhumane existence bound only to its former humanity by the now disembodied, undying mortal heart."

- Codex

Battle
The battle takes place atop a ruined skyscraper on earth. Unlike its form in Doom 2, the Icon of Sin in Doom Eternal has a full body and can attack the player directly by slamming its fists down on the arena, shooting fireballs from its forehead, or sending out waves of fire. In the first phase, the player must attack eight different areas on its body - the right pectoral, left pectoral, right shoulder, left shoulder, right hand, left hand, belly, and head - in order to break off its armor. In the second phase, the battle moves to a different building and the Icon can walk to different sides of the arena to attack. In this phase the player must attack each part of its body again, this time destroying its flesh and exposing the bone and gore underneath. After the last part of its body is destroyed, the Icon collapses on the arena and the player stabs its exposed brain with the Crucible.

Trivia

 * The Icon of Sin's figurine is unlocked automatically after collecting every other figure in the game.
 * The Icon of Sin has clawed feet that are not normally seen during gameplay but can be seen in the model viewer, accessed by activating his figurine.