In order to defeat Darkseid, Flash gained the powers of a God, merging with Black Racer and briefly becoming the living embodiment of DC’s Death.
To kill Darkseid amidst his war on Earth, Flash merged with the living embodiment of Death and became a god himself to kill the powerful villain. In the Darkseid War arc from DC Comics, Barry Allen gained the powers of the Black Racer, leading the hero to kill Darkseid as he unleashed one of his deadliest attacks against the Justice League’s home. However, following the ruler of Apokolips’ death, the dark abilities nearly corrupted The Flash for good.
The Flash has no shortage of incredible powers that have helped the hero against some of the biggest threats in the DC Universe. However, during the Darkseid War, Barry Allen became something else entirely. When Darkseid went to war with the Anti-Monitor on Earth, the DC Comics big bad called for the living embodiment of Death, the Black Racer, to kill his opponent. However, the move backfired when Anti-Monitor made The Flash the new host of Death, resulting in Allen becoming a god.
In The Darkseid War: Chapter Four by Geoff Johns, Jason Fabok, Brad Anderson, and Rob Leigh from DC Comics, Darkseid summoning the New God’s version of Death, the Black Racer, to kill the Anti-Monitor ends with The Flash being merged with powerful being. In his new god-like form, Anti-Monitor uses the speedster and sends him with a powerful boost through Darkseid’s body, killing the villain as he screams out for the Anti-Life Equation. However, while The Flash becoming Death ended up creating one of his most powerful forms, it was also one of his most dangerous.
Justice League: Darkseid War: The Flash #1 by Rob Williams, Jesus Montero, Guy Major, and Saida Temofonte follows up on the shocking death of Darkseid as The Flash struggles with what he’s become. Barry Allen nearly becomes corrupted by Death, which seeks a permanent host for the Black Racer as he briefly becomes a god and outruns the powerful force before separating from it. But, for a brief time, The Flash becoming Black Racer gave him the powers needed to kill Darkseid, which is among the deadliest actions the speedster has ever done. Killing the supervillain showed the true power The Flash had in his darkest role.
Thankfully for the rest of the DC Universe, The Flash’s time as the Black Racer ended relatively swiftly, as the entity would later find a new host and disappear. However, as the living embodiment of Death, Barry Allen’s new powers, combined with the Anti-Monitor, made him strong enough to kill Darkseid as he unleashed his biggest war on Earth to date. The Flash becoming a literal god proved enough to stop Darkseid, although the villain would eventually return in later stories, as he always does.