History: Grom rose to be the leader of the Warsong Clan on Draenor before the Dark Portal ever opened. He was one of the first orcs to drink the blood of Mannoroth, which gave orcs their green skin and the power to invade Azeroth. The Warsong Clan was left largely untouched by the second war between humans and the "old Horde", but after the war, they allied with the Bleeding Hollow clan to steal some of Azeroth's magical artifacts. But after the Dark Portal was closed, Grom and his clan were trapped in Azeroth with no way back. They settled in the wilds of Lordaeron and hid there for fifteen years.
Grom was afflicted by the same demonic curse as all the orcs, and since he was cut off from magical energies in Lordaeron, he began to languish. Unlike most other orcs, he fought the curse and kept himself and his clan out of the human internment camps. Nevertheless, it looked pretty bad for the Warsong orcs until a young orc named Thrall, who had been raised among humans, arrived at their doorstep. Grom took Thrall in and taught him about the ways of the orc clans. This helped unite Thrall's Frostwolf clan with the Warsong orcs. Together with Orgrim Doomhammer, the two clans freed orcs from the Lordaeron internment camps before traveling across the sea and settling in Kalimdor.
But Grom began to feel the pull of the curse even in his new land. Thrall noticed that he was getting restless and sent him to Ashenvale to clear some land for a new settlement. Unfortunately, this angered the night elves, who attacked. The orcs had a druid to run the flag, so they won the WSG game, but their graveyard camping angered the demigod Cenarius. Cenarius fought the orcs, who soon discovered that the demigod couldn't be hurt by conventional attacks. It looked like the end of the line. Luckily for Grom, a troll witch doctor discovered a fountain of blood that gave super strength! How very convenient! In fact, the blood was Mannoroth's, and although he knew Thrall would be against it, Grom drank the blood and made his orcs do likewise. They defeated Cenarius's forces and lived to fight another day.
Unfortunately, that other day came really quickly. After the battle with Cenarius, Mannoroth appeared and used the power of his blood to control Grom and all the Warsong orcs. Mannoroth sent Grom to attack Thrall and the humans he had allied with. Thrall and a group of Tauren captured Grom and completed a ritual to free him from Mannoroth's control. After being freed, Grom was extraordinarily angry at Mannoroth, and he and Thrall set out to hunt down and kill the demon.
Thrall and Grom found Mannoroth in the Demon Fall Canyon area of Ashenvale. Mannoroth knocked Thrall out and was about to finish the duo off when Grom hurled his axe into Mannoroth's chest. Mannoroth exploded in a burst of hellfire, which also hit Grom. Thrall raced to Grom's side, and watched his best friend die even as Mannoroth's curse lifted from all the orcs. Grom had freed them from their demonic corruption and saved the Horde.
Where he is now: He's definitely dead, but his presence lingers everywhere. Thrall sits in Grommash Hold in Orgrimmar, which is adorned with Mannoroth's armor (complete with axe hole.) The Horde's outpost in Stranglethorn Vale is called Grom'Gol. Members of the Horde honor Grom every year by leaving a candle at his grave in Demon Fall Canyon. The monument to him there reads, "Here lies Grommash Hellscream, Chieftain of the Warsong Clan. In many ways, the curse of our people began and ended with Grom. His name meant "Giant's Heart" in our ancient tongue. He earned that name a hundred fold as he stood alone before the demon Mannoroth -- and won our freedom with his blood. Lok'Tar Ogar, Big Brother. May the Warsong never fade."
Identifying characteristics: Grom was a thin, green orc with black tattoos on his chin. He was also a Blademaster, which means he used swords as well as his famous axe Gorehowl.
Why he lives on: Grom's son, Garrosh, remained behind in Outland after Grom crossed over to Azeroth. He has risen to become a leader of the Mag'Har orcs in Garadar. However, he is depressed because the chieftain of the tribe is dying and because he's ashamed to be Grom's son. The last Garrosh knew of his father was as the first orc to become corrupt. However, after a very long quest chain in Nagrand, Thrall comes to Garadar and shows Garrosh a spirit re-enactment of Grom's fight against Mannoroth, and tells him his father was a hero. This makes Garrosh feel better, and he gives all Horde in the zone a buff called Warsong Hellscream (identical to Warchief's Blessing.)
Find out more at: WoWWiki on Grom, Wikipedia on Grom, the cinematic of Grom and Thrall fighting Mannoroth, WoWWiki on Garrosh.
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