I just recently started working on an abzan seance deck as well, and holy crap that card is powerful. There are so many possibilities on how to build this that I feel like I just barely started scratching the surface.
Here's what I figured out so far:
- 4 x
satyr wayfinder seems obvious, while the number of
necromancer's assistants I'm unsure about. Exiling an assistant with seance increases the number of creatures in the graveyard if the deck is more than 1/3 creatures, allowing seance to fuel itself, while at the same time digging for spider spawning and vengevine. Playing him from hand also helps find the first seance, with
treasured find. Maybe it's correct to play the max amount of assistants and treasured finds just to maximize the chance of finding seance.
-
spider spawning is great if you fail to find seance; with a seance in play you can either abandon the spider plan entirely (exiling your creatures to get immediate value) or use seance to fill the graveyard by evoking wayfinders and assistants. Against white decks that might have
planar cleansing, this second plan seems much safer, as you can make a lot of spiders after the board has been wiped.
- the most powerful enter-the-field abilities are on
rune-scarred demon and
shadowborn demon, which should be auto-inclusions. The others are mostly lifegain (
lone missionary and
saruli gatekeepers) so I decided to play a single
angelic accord, with the idea of tutoring it up with the demon or the treasured find when I get my engine going. So far it's been very good, although it's not a good thing to do against
planar cleansing decks
-
Liliana's specter is interesting but the double-black cost has deterred me from it so far. I have a couple
blister beetles, another nice seance target that helps survive against
loyal pegasus.
Reclamation sage doesn't seem necessary as artifacts and enchantments don't seem to give any significant trouble to this deck.
Attended knight and
elvish pioneer seem pretty irrelevant.
- I tried
Bloodflow connoisseur which turned out to be surprisingly awesome, putting creatures in the graveyard when you need to reanimate them, circumventing exile effects and
arrests, sacrificing the seance tokens, vengevine, any spiders sent on a suicide attack, and in general being a gigantic creature that must be chump-blocked every turn.
- I also have three
gravediggers, which seemed superfluous at first. However I found that they really help in all stages of the game, with or without a seance in play; they can be used to get a second use from satyrs when you don't have seance yet, they give you a connoisseur when you need her, they allow you to re-cast shadowborn demon basically as many times as you want, an d they easily trigger vengevine. Something similar goes for
rescue from the underworld, of which I have 2 copies.
My Seance deck actually gets by on just 4x Satyr. It usually fills the GY well enough on its own, supplemented by early trades/chumps and Seance itself. Some people aren't comfortable cutting Necromancer's Assistants, but I don't run any and generally don't have problems keeping my yard stocked.
I ran Specter for awhile, as it is a good card, and works well with Seance. Sadly, the colors mean there will be times where you occasionally can't play it. I also noticed that in a lot of cases, by the time you get your Seance engine up and running to be able to bring them back, the discard aspect is dead (since opponent has no cards, or are hanging onto cards they can play in response to get rid of). Of course there are times where it is relevant in the late game, but it didn't seem worth it to me. Results may vary.
I actually run a single copy of
Attended Knight as mise as it can often help stall in the early game against fast decks. Putting two creatures on the board (one of which has First Strike) can be a pretty big roadblock for certain decks, and just like everything else, comes back with Seance and gives you virtual CA by producing another 1/1 token that sticks around.
I run two copies of
Elvish Pioneer in the deck as well. The ETB is usually pretty irrelevant late game, even with Seance. That said, the deck runs a decent number of bombs and they do often help to ramp into things a little earlier than usual, leaving behind a 1/1 to chump with and fill the yard. It allows to deck to sort of play the pseudo ramp game in situations when you don't draw or can't play Seance.
Kor Cartographer can work in this capacity as well, but it a little slower (albeit more consistent).
Bloodflow Connoisseur is a card that I have wrestle with quite a bit. Me and Hakeem have discussed it over on the WotC boards when I first posted the old version of my deck there. They do in fact work great with Seance, with each activation giving your a +1/+1 counter. They also help to fill the yard early, and convert stuff like
Elvish Visionary into tangible threats. I originally ran 3 copies of Connoisseur, but the more and more games I played with the deck, the more and more of them got cut, until I wasn't running them at all anymore. For all their advantages, they are terrible being cast onto an empty board (uncommon in this deck, but it happens), they are often worse when drawn in multiples, they are extremely weak to bounce and hard removal (which can often put you down on CA if you aren't careful). On top of that not having an ETB makes them terrible with Seance, and every one of them you see go to the yard (via mill/trades/removal) will make you sad when you get that Seance down and realize bringing it back does nothing for you at all.
As such, if I were to run
Bloodflow Connoisseur in the deck (which I DO think is perfectly valid/viable) I would probably try and limit it to a 1-2 of. Just to try and reduce how often they end up in the GY where they do nothing for you.
Seance decks are pretty fun overall, and I personally think Abzan is the place to be to make the most of it.