I think it’s very unlikely to get metalcraft. Ichor wellsprings are usually sacrificed quite soon after you get them out (to [[Makeshift Munitions]], [[Annihilating glare]] or [[Deadly Dispute]]) and Myr Servitors don’t always come in multiples and are easy to kill. I suppose with more artifact lands you could get there, but that leaves you much more vulnerable to artifact hate.

That’s cool to hear! I’m very new so I don’t have a sense of history yet. It’s going to be a fun ride!

I think carrion feed is a good idea, at least, but I would be careful about going too deep into pure sac outlets. The Groff and the Morkrut Behemoth are already doing double duty as good manifest targets and sac outlets (and decent topdecks). Higher creature density makes manifest better in general, though.

I worry that without sufficient card draw or filtering you can end up with some pretty dead hands. Perhaps [[Elven Farsight]] is a safe inclusion that will always be helpful and is great for setting up manifest, too.

I couldn’t help myself. I threw together a decklist based on Sultai Emissary

Sultai Emissary and [[Bayou Groff]] have really good synergy. The Groff is a great manifest target and it can sac the emissary if you play it normally, but I don’t quite see how I can make this work as a deck. It seems most people tend to want to abuse manifest by manifesting something huge and flickering it, but I feel that that line of play is a little bit too convoluted to be worth it, although it is nice that [[Soul Summons]] and [[Ephemerate]] are both white.

I think the trick to playing the Emissary is to have a decent volume of OK manifest targets in the deck, some sac value stuff and not overthinking it too much beyond that.

[[Scythe Tiger]] and [[Rogue Elephant]] are also good value manifest target, but their ETB effects are not so nice if you have them in hand. Perhaps in a sacrifice oriented deck they could be worthwhile if you just sac them as they ETB to trigger something like [[Mortician Beetle]]? Flipping a manifested Tiger in response to a removal spell is quite sexy, though.