Basically make sure you are a geared DK tank or DPS doesn't matter but tank works better.
Make sure you have H gurth although other gurths work just won't be the same results
On H spine gather a ton of bloods towards the end 2 or 3 tendon
gather them up in a big group near the tendon before it opens
pop unholy blight and ams
about 50-100 tentcles will spawn
target the tendon and use the sword (Forgot the name) along with instant dots and BB
all the tentecles will attack the tendon
it will do the most damage to the tendons over ANY class
You can also do this in any large AoE fight
for example at the end in stonecore with like all teh little adds that can be 1 shot just run through them gather them up in a large bunch pull the boss use unholy blight a shit load of tentecles will spawn and 1 shot the boss (Works in Heroic and normal mode)
can do this on fights like Yosi too but make sure your raid doesn't attack them (this is fun for ranks on wol)
basically the more adds the more tentcles will spawn, this is best on H Spine as it can also be used as a D/c
if you hold all the bloods till the 3rd tendon making sure your raid doesnt kill them except the 10 that is needed you can pop unholy blight and it will lag everyone or d/c a few with poop pcs