Well here is my list idea i think its solid only issue is the elite's, can't really pick which one will work better so maybe 3 of each?
HQ 535
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Keeper of Secrets 270
Greater Reward,Exaulted Reward,lvl 3
Herald of Slaanesh 75
Greater Reward,Locus of Grace
Herald of Slaanesh 75
Greater Reward,Locus of Grace
Herald of Tzeentch 115
Greater reward,exalted locus of conjuration,lvl 2
Elites 140
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4 Fiends of Slaanesh
Troops 645
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20 Demonettes 205
Alluress,Lesser Reward,Insterment
20 Demonettes 205
Alluress,Lesser Reward,Insterment
20 Pink Horrors 235
Iridecent Horror,Blasted Standard,Insterment
Heavy Support 660
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Demon Prince 240
Slaanesh,wings,Greater reward,warp armour,lvl 1
Demon Prince 240
Slaanesh,wings,Greater reward,warp armour,lvl 1
Soul Grinder 180
Slaanesh,Pleghm (mmhmm Rending Pleghm)
2000