Invincible faces off against Powerplex, a regular human using stolen technology that allows him to absorb any type of energy and then redirect it. In order to lure Invincible to fight him, Powerplex uses his own family, with his wife’s consent, to act as hostages. Powerplex hates Invincible because his sister died as collateral damage during Invincible and Omni-Man’s fight in the city.
During the fight, Powerplex unleashes all his power to kill Invincible, not knowing that the entire floor was charged with his power as well, instantly killing his wife and son.
From – Invincible #59