Why Did Icarus Fly into the Sun?

Feeling frustrated over his failure to fulfill his mission and guilt over his actions, Ikaris left Sersi, flying off into the sky. Ikaris flew off into space and after feeling his life had no purpose as he had betrayed his mission as an Eternal, flew straight into the Sun.

Why did they kill off Icarus?

Despite obvious similarities to characters like Superman, he lacks the Kryptonian's invincibility. More than that, he is driven to suicide out of sheer regret. "I think he's sorry for the way he lived his whole life on this planet," Kaz told CBR. "And that's a lot of burden to carry.

Is Icarus dead Eternals?

So yeah, he's dead." However, as we've seen with the events of Avengers: Endgame and Loki, characters being dead in the MCU is played as such that makes use of the word "definitive" very loose. We may never see this Ikaris portrayed by Richard Madden ever again.