For my taste, I like 6 slots of dampened spirits for the tohit debuff, endurance reduction, and recharge. Six slots of Dark Watcher's Despair is about the same. Especially since you plan to re-slot at level 47, Dampened Spirits is very inexpensive and effective. It's all about the tohit debuff, baby.
Triumphant Defenders Forever
Psylenz FF/Psi, ArticQuark Storm/Rad, Symon BarSisyphus Bots/psn, Max VanSydow Thugs/Dk, Cyclone Symon Bots/stm, Blue Loki Ice/Cd, Widow 46526
HelinCarnate:OMG it is so terrible. I have the option to take 3 more powers but no additional slots. Boo F'ing hoo.
On my fire/dark corruptor I slotted 4 cloud senses (to hit debuff, acc/to hit debuff, acc/rech, to hit debuff/end red/rech) and a siphon insight (acc/end/rech) for the global recharge in cloud senses (6.25%) plus the accuracy that the regular to hit debuff sets do not have. This gives me 60% acc, 57% rech and 44% to hit debuff plus some end reduction. However cloud senses are not cheap these days, so psylez's suggesions are not bad although the lack of accuracy might be an issue - you might consider 5 dampened spirits plus an accuracy IO. I don't know if mm supremacy affects pets in secondaries or not - if it does, then you won't have to worry about accuracy as much as a corruptor.
Globals: @Midnight Mystique/@Magik13
Clouded senses is a good set for the dark servant, too, just not as cheap.
Triumphant Defenders Forever
Psylenz FF/Psi, ArticQuark Storm/Rad, Symon BarSisyphus Bots/psn, Max VanSydow Thugs/Dk, Cyclone Symon Bots/stm, Blue Loki Ice/Cd, Widow 46526
HelinCarnate:OMG it is so terrible. I have the option to take 3 more powers but no additional slots. Boo F'ing hoo.
I go with 4 pieces of the Cloud Senses accurate tohit debuff set, and two IOs of the accurate healing set (any two of them with healing would do). It rounds out his accuracy, end redux, recharge, tohit and gives him a slightly higher heal for when you are in range.
"An army is a team. It lives, eats, sleeps, fights as a team. This individuality stuff is a bunch of BS." -General George Patton
-Lord Azazel
I'm getting close to getting Dark Servant for the first time on any character and looking at what all he can do I'm sort of at a loss on how to slot him. I know he needs recharge since the MM version isn't permanent out of the box, and I'm assuming I need a generic Accuracy IO since the various debuff sets only affect pet powers that have that effect. But other than that, what's a good way to slot him until I can use Hami-Os?
I was thinking of just going Acc / 3x Recharge / Hold / To-Hit Debuff (all level 40 generic IOs) but there may be better slotting options. Once I hit 47 I'll probably go with Hami-Os, something like 2 Acc/Mez, 3 Recharge/Defense/To-Hit Debuff, 1 Heal/Endurance.
Cascade, level 50 Blaster (NRG/NRG since before it was cool)
Mechmeister, level 50 Bots / Traps MM
FAR too many non-50 alts to name
[u]Arcs[u]
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