So, time to get back to work on these guides.
Hyjal summit is a rather nice instance, open air and all that. Good scenery, lots of unavoidable trash (for once), and mildly challenging bosses, so, all in all, a good raid.
Feign death: If you FD for too long, bosses will do x10 damage. Beware.
Just remember to stay at max range: his death and decay will kill you quickly. If you are rooted, master's call can save your life.
He is easier without npcs to assist you. Simply dps him down and FD after infernals spawn (but don't stay down for long!). Widow venom should help, he heals himself a lot.
Stay more than 20 yards away from him to avoid his nasty debuff. The training dummy puts up a better fight.
Requires (unless seriously overgeared) a spirit beast. That means BM. Since Archimonde requires a lot of self-healing... I'm not sure spirit beast would be enough.
Easy strat, just put the boss between you and your pet, and go 99 yards away from your pet. That way, the boss will be at 99+3 to 99+5 yards away from you, and won't cast doom on you. Use hunter's mark to know when you are safe.
Find a tree. Get under it. It will avoid his bumps. Now, dps him as fast as you can before grip of the legion kills you. A restorative potion can give you time to bandage and avoid some damage.