Grog is a Heliopolitan who served Seth faithfully during his war on Asgard.
Grog was created by Tom DeFalco and Ron Frenz in 1988 and first appeared in Thor #390.
During the initial stages of Seth's war with Asgard, Grog was dispatched to Earth with a contingent of soldiers to kill Thor. Grog and his troops were defeated by Thor, Black Knight, and Captain America (Steve Rogers). Grog was sent to the Vault.
When Thor realized that Asgard was in peril, he freed Grog from the Vault and together with Hogun, Black Knight, and Earth Force, he travels to Seth's Dimension of Death. Grog successful defeated Thor when Balder removed Thor's godly powers from afar. Thor and his companions were tortured but eventually broke free. Thor was then able to free Bes, the Egyptian god of luck who Seth had used to manipulate probability, and his father Odin.
During a titanic battle between Surtur and Thor, the Black Pyramid in which Grog was station was destroyed. It is presumed that Grog died, but since he works for the Egyptian god of death, he will likely resurface.
Grog faces Thor who was said to be in a weakened state after his exile from Asgard. Thor defeats and kills Grog when he decides to let loose during their fight.
Like all Heliopolitans, Grog is immune to disease and aging, heals quickly, and has super-human strength. He is a skilled combatant and often wields a power lance which can fire blasts of unknown energy.