A'lars is the second son of
Kronos and Daina, two of the first generation of the
Eternals, and was born eons ago in the city of Titanos. A'lars and his brother
Zuras were raised in the aftermath of the great civil war which divided the first colony of Eternals. Their father, Kronos, who was on the winning side of the civil war, toiled away in his laboratory attempting to discover the secrets of the self-regenerating cosmic life force that he felt his race was capable of attaining. A force field cylinder containing cosmic energy exploded, disintegrating Kronos' body and giving immortality to all nearby Eternals. A'lars then became a scientist like his father. A'lars and Zuras, both adults at the time of Kronos's death, held a general assembly to determine who would succeed him. The assembly chose Zuras, so A'lars chose to leave the colony to avoid the sort of fraternal rivalry that led Kronos and his brother
Uranos to the first civil war. He settled on
Saturn's moon
Titan, taking over as leader of the underground colony that his uncle Uranos had built centuries earlier. Upon arriving on Titan, A'lars discovered the
Uranian Eternal
Sui-San, the sole survivor of the civil war that destroyed the Eternals of Titan previously. Sui-San bore two children for Mentor,
Thanos and Eros (later known as
Starfox). Sui-San died in Thanos' first major attack against Titan. Mentor later meets
Rick Jones and
Captain Mar-Vell. With his son Eros, he informs Jones and Mar-Vell of Thanos's degradation of Titan. Mentor enlists Mar-Vell's aid against Thanos. Mentor is imprisoned by Thanos, but freed by Mar-Vell. Mentor joined in the battle against Thanos. Later, Mentor joins in the attempt to cure Mar-Vell of cancer, and attends Mar-Vell's last hours. Thanos escapes captivity and reclaims his
Black Order forces from
Corvus Glaive. After retaking command of his Black Quadrant outpost, Thanos discovers that he is dying. Thanos tries to force Mentor to find a cure for his malady, but kills him when he is unable to. A'lars is later resurrected and trapped in the Exclusion, a pocket dimension where the Eternals are resurrected after death. ==Powers and abilities==