Quick details about the team...

DK + 4 Elemental Shaman

DK Talent build: http://www.wowarmory.com/character-t...ion&n=Ellianaa

Shaman 1 Talent build: http://www.wowarmory.com/character-t...gion&n=Haachoo

Shaman 2-4 talent build: http://www.wowarmory.com/character-t...Legion&n=Hachu

My playstyle is really just instinct. I don't have any hardcoded castsequence. All 4 shamans DPS, and I simply start spamming my LHW on tank button as my tank needs healing (it does not /stopcasting, it just picks up after the current cast). I use chain heal x4 as well to heal my shamans, each shaman chain heals the next shaman in the sequence with the last shaman chain healing the first shaman (not the tank).

I open every fight with Flameshock + Lava burst as you can see, and then from there I do one of two things:

If its a 1-2 mob pull, I simply spam LB (and only LB) until the mobs are dead

If its 3+ mob pull, I use a castrandom:

/castrandom Lava Burst,Lightning Bolt,Chain Lightning,Purge

Aside from that as I said above I play on instinct I've gotten to the point where I know my team very well so I know when to heal, when to use cooldowns like icebound fortitude, etc.