In broad strokes, here's my advice for SO slotting in Dark Miasma. For the most part it likely won't be significantly different from those old guides you mentioned and you should probably use those as good reference. Aside from ED considerations and IOs (which you aren't using), they should be accurate. That said, on to the overview:
A lot of this depends on what else you have in play (Stamina, Hasten, Leadership, etc) and what your playstyle is like.
Tar Patch: 2-3 Recharge
Twilight Grasp: 2 Accuracy / 2 Recharge / 2 Heal
Darkest Night: 2-3 Endurance Reduction / 2-3 ToHitDebuff
Howling Twilight: 2-3 Recharge / 2-3 Disorient
Fearsome Stare: 2 Accuracy / 2-3 Recharge / 1-2 Fear / 1-2 ToHitDebuff
Shadow Fall: 2-3 Endurance Reduction / 2-3 Resistance / 2-3 Defense
Petrifying Gaze: 2 Accuracy / 2 Recharge / 2 Hold
Black Hole: widely skipped, but if taken 1-2 Accuracy / 1-2 Intangibility depending on how you intend to use the power
Dark Servant: 3 To Hit Debuff / 1-2 Accuracy / 1-2 Hold / 1-2 Heal
As I said at the start, a lot of this is influenced by whether or not you have Stamina (need less EndRedux), whether or not you have Hasten (need less Recharge), and whether or not you're running Leadership (need less Accuracy and possibly more EndRedux). The above should serve as a rough outline though.
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I have a level 20 Dark Miasma / Dual Pistols Defender that I could use some leveling advice with. I've looked at several Dark Miasma Defender build threads, but they're all geared to IOs. The last Dark Miasma Defender build guide I can find with SOs is dated back to Issue 6. Is there any advice as to how I should slot out Dark Miasma powers with SOs that I can use while leveling mine? Thanks.
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