This quest is not available in game.
Darren Malvew of Southshore wants you to kill 8 Mountain Lions and 10 Hulking Mountain Lions.
Ain't nothin' that irks me more than losin' these here beautiful horses. And believe me, we've lost quite a few between them pesky undead creeps, the dang Syndicate gang and all the other good-for-nothin' scoundrels pokin' about these parts.
But I swear on my ol' grand-daddy's grave there ain't no bigger menace to our horses here than them Mountain Lions up in Alterac. Always comin' down from the hills and makin' my life difficult!
You fancy yourself a hero? Go and do somethin' about it then!