My method for taming
Karkin (50959) and
Skarr (50815) is to Silencing Shot, pop Deterrence, and then Tame Beast. With enough haste and/or the right speed of button mashing, this method will work because of the downtime of their Fieroclast Barrage casts. I would HIGHLY recommend having a high haste rating for these tames, as it will cause Tame Beast to cast more quickly, which is definitely needed for these tames. Either reforge, buy haste gear from the auction house, use haste on use trinkets, or simply buy food and potions that give you haste to up your haste rating. They both spawn on Fireplume Ridge, Karkin spawning closer to Ragnaros' Reach, and Skarr spawning closer to The Furnace. Both pets are non-exotic, and can be tamed by any hunter. They are all level 85, and cannot be found unless you have completed up to the quest Tortolla's Revenge in Mount Hyjal, and have started the daily questline at the Sanctuary of Malorne far enough to get into the Molten Front through the portal in the Regrowth. The portal opens after you turn in your first set of 20 Marks of the World Tree.
I've added a map here with all of their names and images, as well as a dot for where each of them spawn that is color coordinated with the ring around their image. I hope this helps in locating them for some. I put the dots this way, as I did not want to stack them on top of each other, but the two rares DO switch spots from time to time. I've just seen them this way more often. That doesn't mean you shouldn't check both though, as I happened to tame both personally on Karkin's white dot.
