DS/Ruin is an upkeep rotation with a filler. Four effects stay on the boss: a curse, a bane, Corruption and Immolate. Shadow Bolt fills the time between, and Life Tap buys the mana.

Before the pull

• Summon your Imp and sacrifice it with Demonic Sacrifice. Burning Shadow lasts two hours, so do it well before the pull, and don't summon a demon afterwards: any summon cancels it. The sim starts every fight with the buff up.
• Keep Demon Armor on. It adds armor, not damage.
• Life Tap a second and a half before the pull is the list's only pre-pull line, worth 0.0 %: inside the noise, so skip it if you like.

Priority

There is no fixed order here. When you are free to cast, scan down and take the first line whose condition is true.

Beside each line the widget gives its casts and what it adds. In words:

1. Life Tap below 10 % mana. Each tap turns 424 health plus your Spirit into as much mana, 20 % more with Improved Life Tap. Tapping only when nearly empty means none of it spills over a full bar. Life Tap's line carries 27.9 % of the three-minute score. On one-minute fights the line waits for 5 % and is never needed.
2. Curse of the Elements whenever it is missing. The boss takes 10 % more magic damage from every caster. The sim's raid leaves it to you, and it is worth 6.7 % to your own damage. Two warlocks' copies don't stack, so if another warlock holds it on the boss, skip the line.
3. Bane of Doom while a minute or more is left (two- and three-minute fights). Its single hit lands 60 seconds later: 1,742 plus 400 % of your spell power. That is a little more damage a minute than Bane of Agony, for one global cooldown a minute instead of two and a half. You hold one bane per boss, so Doom and Agony take turns. On three minutes this line adds 3.1 %.
4. Bane of Agony once Doom is off the boss and Agony has run out. That is the last minute of a fight, or all of a one-minute fight. Its ticks start at half strength and end at one and a half times, and the sim only recasts it after it ends. It is worth 12.2 %.
5. Corruption as it runs out. With Improved Corruption its 2-second cast drops by 0.4 seconds a point. It is worth 11.0 %.
6. Immolate as it runs out. It is Fire, so Burning Shadow, Improved Shadow Bolt and Malevolence don't touch it. Its line is worth only 3.3 %, because without it that time goes to Shadow Bolt.
7. Shadow Bolt the rest of the time. It is 47.3 % of your damage, and each crit puts Improved Shadow Bolt's 20 % back on the boss.
8. The last seconds. Searing Pain goes out in the last 3.5 seconds and Shadowburn in the last 1.5, because Shadow Bolt's 2.5-second cast no longer fits. On a real boss, use them as it dies.

On one-minute fights Shadowburn also goes out on cooldown, about 4.0 times a minute, for 0.7 %. Each one costs a Soul Shard in game, which the sim doesn't count, so bring them.

More than one target

Against three bosses the rotation becomes a DoT spread. Each boss gets Bane of Agony, Corruption and Immolate, while Bane of Doom, Curse of the Elements and Shadow Bolt stay on the main boss. On a three-minute fight against three bosses Corruption alone is 30.5 % of your damage and Shadow Bolt falls to 12.8 %, against 54.9 % on one boss. The Agony lines on the second and third bosses are worth 6.7 % each. Searing Pain starts a little earlier at the end, and the three-minute list drops Shadowburn with the talent.

Cooldowns

Nothing in the DS/Ruin kit is a damage cooldown. The sim times a trinket, mana and a bane:

• Talisman of Ascendance at the pull and every minute after. Each spell you cast in the next 20 seconds adds a 40 spell damage stack, to a maximum of five.
• Major Mana Potion at 75 % mana or less, the first about 12 seconds in, and Demonic Rune at 60 %, on its own two-minute cooldown. Their lines score nothing, because the sim drinks both anyway, but the mana counts: the potion is worth 1.8 %, the rune 0.8 %.
• Bane of Doom comes back every minute: the opener, then a recast about a minute in on the longer fights.
• Racials. Trolls press Berserking and Orcs Blood Fury at the pull, and again whenever they come back.

Cooldown	Uses	At
Talisman of Ascendance	1	0:00
Amplify Curse	1	0:00
Major Mana Potion	1	0:12
Demonic Rune	1	0:24

What your log should show

Put your own Warcraft Logs numbers next to these: casts a minute, damage share and crit rate for each spell.

Ability	Casts per minute	Of damage	Crit
Shadow Bolt	14.4	47.3 %	22.5 %
Bane of Agony	3.3	16.4 %	22.4 %
Corruption	3.3	15.4 %	22.4 %
Immolate	4.1	10.4 %	17.6 %
Shadowburn	4.0	8.9 %	22.2 %
Searing Pain	1.4	1.6 %	28.2 %
Demonic Rune	1.0	–	–
Curse of the Elements	1.1	–	–
Talisman of Ascendance	1.0	–	–
Amplify Curse	1.0	–	–
Life Tap	1.0	–	–
Major Mana Potion	1.0	–	–

Your log should have about 14.4 Shadow Bolts a minute against 1.0 Life Taps, and Corruption should land close to 15.4 % of the damage. Fewer Shadow Bolts usually means time lost to movement or to late refreshes. Expect Shadow Bolt's crit rate to run above your character sheet: Malevolence's bonus applies to Shadow spells and isn't part of the sheet's figure.

Uptimes

Buff or debuff	Uptime	Times per fight
Bane of Agonyon the boss	92.4 %	3.0
Corruptionon the boss	89.8 %	3.0
Immolateon the boss	80.8 %	3.8
Shadow Vulnerabilityon the boss	40.9 %	3.0
Ascendance	34.0 %	1.0
Ascendance	33.3 %	1.0
Amplify Curse	2.9 %	1.0

Burning Shadow should read 100.0 %: anything less means a demon was summoned in the fight. Corruption should sit near 89.8 %.

Improved Shadow Bolt's Shadow Vulnerability is the one that moves with your crit: about 40.9 % on this fight.