I've Gone and Made a Mess (25 player)

I also posted this on the page from the boss itself, so this is copy+pasta:

I haven't seen it written down here somewhere yet, but a good tactic for 25man is to let the first one or two people who get Mark of the Fallen Champion die as soon as possible.

Die? What did you say? Die?

Yes die!

For every person alive with Mark of the Fallen Champion on him, Saurfang gets one extra blood point. With 1 mark up, he gets 2 bloodpoints instead of 1 on each tick, with 2 marks up he gets 3 points each tick, etc. That's why marks keep coming in faster and faster during the fight, until your healers can't keep up anymore.

If you let the first one or two people who get marked die, the following marks will come in on normal rate (like the start of the fight).

When we figured this out, the fight became incredibly easy and we got the achievement I've Gone and Made a Mess (25 player) without any hassle and the 10 player version an hour or so later.

This achievement is like A Quick Shave - it's possible to kill the boss without getting it, but most farm kills are going to earn the achievement.

My guild got a total of 6 Marks with the "heal the Marked" strat (go-go Beacon of Light) on our (clean) first kill, so even a bit of luck for an average guild will get this achievement, no special strategies or crazy over-gearing required.

Assuming this will be like Moroes' Garrote.