Looking at our opener, it removes a couple Demonbolt casts so we aren't past the cap. I believe for Single Target it should just then be:
Demonic Empowerment - Prepull
Demonbolt - Prepull, (praying for Demonic Calling proc) [4 shards after cast]
Doom
Demonbolt (praying for Demonic Calling proc) [5]
Doomguard [4]
Demonic Empowerment
Demonbolt (praying for Demonic Calling proc) [5]
Hand of Gul'dan [1]
Call Dreadstalkers [0-1]
Demonic Empowerment
Thal'kiel's Consumption
(priority as usual)
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If you have talented Hands of Doom, perhaps:
Demonic Empowerment - Prepull
Demonbolt - Prepull, (praying for Demonic Calling proc) [4 shards after cast]
Hand of Gul'dan (applying Doom) [0]
Demonbolt (praying for Demonic Calling proc) [1]
Doomguard [0]
Demonic Empowerment
Demonbolt (until 2 shards or Demonic Calling proc, whichever occurs first)
Call Dreadstalkers [0-2]
Demonic Empowerment
Thal'kiel's Consumption
(priority as usual)