I will say at this point that Sectarus + Rise Again reads as a very economical counter to swarm play.
I'd just like to point out that Sectarus can cast its curse only after damage has been dealt.
So, if the creature was killed it's too late to cast Rise Again.
If the creature is not killed you can cast Rise Again but I would say that you cast it too soon at that point as it will very likely be Seeking Dispelled once your opponent has an idea what you're up to.
So Rise Again does not really fit on Sectarus, imo
Better to QC Rise Again from your hand right before you finish the creature off.
Depends. If you think you might kill the creature with Sectarus, then you can QC it first before attacking. But if you have several friendies (e.g. zombies or skellies popping out of Libro), then you could use Sectarus to stick the Rise Again, then let your friends finish the creature before the end of the round. Of course, if that's your plan you could just use Ziggurat with a zombie swarm instead.
Anyway, I've had a lot of success with Sectarus on an
Araxxian Crown Warlock. More life, hits harder (Battle Skill), has Curseweaving (pseudo-Cantrip on 1 curse per kill), and gets a cheaper Battle Forge (since he's basically a melee mage + a Blood Reaper buddy).
You could also try it on
Adramelech Warlock with Demonhide Mask (to get a pseudo-Vampirism via Demonic Reward) and a buddy that deals Flame damage; e.g. [mwcard=MW1C01] Adramelech, Lord of Fire[/mwcard] or [mwcard=MW1C16] Flaming Hellion[/mwcard] or something. Sectarus won't directly benefit from Smoldering Curses, but will at least empower your Flaming buddy, who in turn helps your Demonic Reward (or you can just use [mwcard=MWSTX2FFI05] Ignite[/mwcard]). But I personally prefer the AC Warlock's Curseweaving and Battle Skill.