Originally Posted by manly

Well, cooldown stacking always depends on a number of factors. First, your gear choice (ie: SCB trinket or not, lots of haste gear etc.), then group comp (for mana regen planning), then a bunch of other factors, such as crit rate affecting your mana returns which might affect your rotations as you go. An absolute perfect execution should look close to this:

1- stack 5 scorch
[...]
2- drums of battle
3- wait for the annoying drums of battle GCD
3- flame cap, skull of gul'dan, icy veins, destruction potion
[~17-18 seconds]
4- combustion (ie: pre-cast combustion)
5- fireball (number of fireball debatable and depending upon crit rate, usually 1 or 2 fireballs)
6- fireball
7- mojo madness

[2 min]
8- drums of battle
9- wait for stupid gcd
10- skull of gul'dan, destruction potion
11- mojo madness

<get an innervate somewhere here>

[5min in the fight]
12- flame cap

[19% minus 1.5 second]
12- drums of battle
13- GCD

[at 19%]
14- bloodlust
15- skull of gul'dan, icy veins, destruction potion
[~17-18 seconds]
16- combustion (ie: pre-cast combustion)
17- fireball (number of fireball debatable and depending upon crit rate, usually 1 or 2 fireballs)
18- fireball
19- mojo madness

[at sub 1% (this is very situational and a judgement call, depends on your current ignite)]
20- scorch
21- fireblast
22- scorch spam

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Theres a few numbers that can be played around depending on a number of factors. The innervate is just to avoid you using that mana gem, but you can live without it. What I would recommend is probably flamecap directly on the pull, managem, then flamecap at 5min, and use a mana potion instead of destro pot at 2min (basically, don't stack any dps consumables on the 2nd set of cooldowns). Normally the timing of bloodlust is much more involved/precise than that, but given the length of the fight its not worth bothering. Also, cooldown stacking varies if you use SCB, since you dont flame cap and use mana gems everytime. It also means you stack combustion with the rest, not 'outside' of everything else.

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Note that I did not mention berserking anywhere. This is because its a judgment call. If you can do it after a meteor, then its more haste. The numbers listed above are not absolute, there some variance on how you time your cooldowns -- you could 'wait for your procs' up to some leniance, because your last set of cooldowns are stacked on the last minute. That means you have ~1min of wiggle room. 'Berserking' is roughly a 'proc' in the sense it can be better in some cases if you can wait for it. I haven't given it much thought given I'm not a troll, but thats what my gut feeling would play with it.