Last night we took down the Ogre King and had our first peek at Gruul. We knew nothing about the fight so we began with the standard "experimental" setup.

1 MT flasked and buffed to a reasonable HP, balanced group with assigned healing. OT's assigned to pick up any possible adds. SPriest and Feral in healing mode. Everyone spreading out for possible PBAE or chain effects a la C'thun. And about 30 seconds into the encounter we met up with Shatter and got 2 shotted.

We went back and enabled our /CTW's and told people to scatter after the knockback. No pets we exclaimed after a Water Elemental Shattered me for about 750 damage. We ran through the event several more times trying to figure out the mechanic of Shatter, but each time we got pretty summarily handled. We experimented with how close you can get without aggroing him, with trying to leash him to prevent total wipes (he can't be leashed), and lots of naked high dives off of the edge of Ruuan Weald while spirit running.

Has anyone been able to figure out what controls the Shatter effect? I don't think it's close-proximity based because the people who killed me each time were nowhere near me. I was a good 20 yards away from the nearest player and I still took 2 shots for about 5k each that killed me... and the people closest to me weren't the people that showed up in my combat log.

Usually with incoming damage, it falls into one or more of 3 categories: Avoidable (a la phase 1 C'thun or Thaddius' Polarity Shift), Mitigatable (a la Vaeleastrasz), or Healable (Loatheb). Does Shatter just fall into one of the latter 2 categories?

I did a search for Gruul and Shatter and returned no posts, so hopefully this is the right time and right place to discuss this.

Shatter actually chains from person to person doubling in dmg each time, we had pretty much the same experience as you, after speaking to a few friends in nihilum it seems that limited invul pots are a great help here and using the full space of the room is the other.

But the bigger problem is the amount of dps needed on gruul to take him down before he gets too big (15 stacks of so) to 1 shot the tank

Hmmm, shatter doesn't seem to chain nor double looking at combatlogs. If it did you would expect to see really huge numbers which you just don't see. Also some attempts there is very very low amounts of damage (less than 100 damage people take) and other shatters all the numbers are several thousand with no low ones.

Also it appears to be distance base off our attempts or I should say at least it seemed to correlate from my personal shatters and looking at the values I was taking. Another thing is that when you shatter both you and the other person take the exact same amount of shatter damage (taking into account zerker/defensive stance of course).

Are you sure about this? From my experience it seemed to be a direct linear relationship between damage taken and distance to people around you (range being 0 to 10k).

Again, I didn't see anything that would suggest a doubling of damage; do you have a combat log etc. that would explain why you came to that conclusion?

I'm not sure if it's a direct linear relationship -- I think it scales differently than that.

But yeah, if you and another player share the exact same X,Y coords, you will take 9000 damage (theoretical max) from each other. I believe the max range is 20 yards. As you get closer to 20 yards apart, the damage drops off. I've seen as low as 300ish.

I've never been good with estimating yards in-game but 20 sounds a bit high to me. I'm fairly confident that the room is large enough that all 25 members can spread out and take 0 damage from each other. Obviously, the knock-around coupled with the slowing down makes that difficult to accomplish during the encounter.

Also the damage can crit which isn't much fun. I've had runs where I get Player A crits you for 12000. You hit player A for 6000. I'm not sure if 'hit' is the right verb but the numbers are accurate.

Edit: if the damage isn't linear what is it? For me it felt like standing about halfway between on top of and max range led to about half damage.

Unless his hitbox is huge, this doesn't seem to make for a very melee friendly fight. You could probably only have 2-3 melee at all on him without bunching up too much.

Well: http://thottbot.com/?sp=33671

I'm pretty sure that yes, it's 20 yards.

My best guess on how the damage works is that you take damage equal to:
[9000 / (20 / [20 - D] ) ]

Where D = Distance.

At point-blank range, you'd take 9000 damage.
At 5yd, you would take [9000 / (20/15)]

[top] 6750 damage.
At 10yd, you would take 9000 / 2

4500 damage.
At 15yd, you would take 2250 damage.
At 19yd, you would take 450 damage.
At 20yd, you'd take 0 damage.

Maybe it's not exactly that formula, but I think it's close.

There's more to it than this -- do the fight first before speculating. There's a lead-up to the shatter, and that involves a ground stomp that sends everyone flying and jumbles up positioning.

Its not. The spell description is 20 yds which is hopefully correct though personally I'm not sure. http://thottbot.com/?sp=33671

I've measured the room to have a diameter of 100-110 yds.

Area of the Room = ~7854 sq yds
Area of 20 yds = ~1257 sq yds

Something interesting though is

Area of 10 yds = ~314

Then this number times 25 is equal to the room's area which of course is since 25*10*10*PI=50*50*PI but wouldn't be surprised if its balanced around that assumption. Reason for 10 yds is because you don't care about the circles have a diameter of 20 yds you are working with fitting into the room but 10 yds since what matters is do these 10 yd radius circles touch either and if they do you take damage then (10yds +10 yds=20yds meaning you are close enough to take damage). This means in theory you can fit 25 circles potentially into this space if you could reshape them into other shapes, but one more additional factor is the circles can be on the edge of the room meaning you need to test for if you can potentially fit 25 10yd radius circles into a circle of 60 yd radius. I know there are formulas for how many circles you can fit into a circle but I sure don't remember them (involves knowing how much wasted space there is when you fit circles as compactly as possible etc).

Lowest damage I've got recorded for Shatter is "Aevi's Shatter hits Jiglee for 77."

Also think I will look at creating a small addon for sending all the player positions when they turn to stone. IMBA had the ability to do that type of thing right up till 2.0 when it broke and I never did add code to display the data.

Are you taking into account the people standing with their back against the wall? I.e. only requiring a half-circle area to fit in as opposed to a full.

Edit: nm, missed it on first glance.

Even if you can't EXACTLY fit everyone in, obviously, there's not much to worry about taking 500-1000 damage.

Well its a little different from C'thun in its asking you can you spread out in ~5 seconds.

You won't have a gruul watcher mod likely anytime soon unless I fix my IMBA position tracking code or someone else looks at what I was doing there and implements something similar. The nice about C'Thun is the ability is close to the range of distances we can already check with InteractDistances which can check distances of ~11yds and 30yds (used to be also ~5 yds but that was for inspect distance which was doubled). The issue with an addon doing something similar to how I track player positions is it requires communicating your coordinates to other players.

You can do 20-25% a minute with properly set-up groups / everyone in hybrid gear. You only need 4-5 healers at the start, no reason not to DPS zerg as quickly as possible.

Limited Invulns are also nice, but I would assume not intended and due for a hotfix.

It isn't quite possible to have 25 people take zero damage, assuming Cryect's estimate of a ~105yd diameter circle. (Note that we're talking about smaller circles with a diameter of 40 yards, not 20, because it's a 20yd radius for the damage.)

Here's a rough sketch I made, more or less to scale. The center of any given circle should not be located inside any other circle. This will make your head hurt if you look at it for too long, but trust me, there are 17 circles. I did this mostly by eye, so perhaps 18 or 19 is possible with true optimization. But still.



Now, if you set a minimum acceptable threshold of, say, 15yd distance for <2k damage per shatter (which is fine, IMO), then I'm certain you can fit 25 circles with a 30yd diameter into this space.

Of course, consistently executing with that margin of error is easier said than done.

Well it's good to know you can fit 25 people with minimal dmg in this room, but the main problem is how to fit them during the fight when :
- you are knockbacked in a random direction/distance 5 sec before the effect
- you are snared during those 5 secs
- you must maintain a (very) high dps during the fight.

Limited invuln pot are obviously a big help since they basically let you avoid 50% of the shatters, but you still have to find a way for the others.

What's the ability/spell name of the knockback?

Yes, planning a strat around your whole raid chain-chugging a pot that you have to go back to Hinterlands and SM to farm up, on top of using every DPS consumable you can get your hands on, certainly sounds like fun to me.

Taken. It's physical damage, look at Thott. BoP would work too.

Wait, haven't I seen this encounter before?

Knock back is "Ground Slam".

@Praetorian: well, in a way it's not really that different from loatheb :) But I agree with you, you can't rely only on that. I suppose you could at least use one on everybody for the first shatter, meaning you would have 2 mins of full dps with no shatter problems.

Taken, but not given (I learned that the hard way via Divine Shield and standing on someone, they were not pleased).
BoP, Invulnerability Potions, Ice Block, all the normal damage avoidance items will prevent damage received though.


Edit - Just to clarify, I still think Invulerability Potions should be used (if at all) in situations where you get an unlucky cluster fuck after a shatter and escape is improbable. Using them on rotations as a raid or basing a strategy around them won't ever be a good strategy to farm content, though it may work for a kill every now and then.

You don't have to chain-chug them if you assume your entire raid isn't incompetent. It could be a nice life-saver for those 'oh shit' moments when for whatever reason you end up too close to someone.