4 Kiku, Night's Flower
Junk on so many levels.
1) FAR too mana-intensive - four mana to destroy a single creature is horribly slow. By the time you could actually use the ability, the game's pretty much decided.
2) As Jacob Orlove already pointed out, the "big" creatures in Oath will thumb their noses at Kiku, having protection from black. About the only maindeck Oath creature that Kiku would be useful against would be Colossus.
3) Stax and Welder will simply outrace you due to mana acceleration and the differences in activation abilities.
4) Decks like Meandeck Tendrils don't run creatures, so Kiku's 1/1 for BB isn't cost effective when your win condition is beatdown (eight 1/1's and four 2/2's aren't going to win the race in Type I).
5) Legendary status - even if Kiku could be considered a decent card, only being able to have one out at a time when your win condition is beatdown is a bad drawback.
Almost anything else would be better in Kiku's place - Nantuko Shade comes to mind first.
I understand that you're trying to incorporate creature control into your deck, but black has better options (Diabolic Edict) than Kiku.
4 Plaguebearer
I understand your fascination with this guy- I'm sweet on him myself - but not for Type I tournament play. He's not going to help you against more than a couple of different decks.
- Oath - getting rid of Orchard spirits wouldn't matter, because Bearer still counts, and you'll never have the mana available to get rid of Oath's real threats (again, most of which are pro-black anyway).
- Stax/etc. - popping Welder is a nice effect, but you can do that with Edicts, too.
- Tendrils - nothing
- Goblins - nothing, as he'll be 'bolted before he's useful.
- Fish - jackpot, if he resolves and survives past Lavamancer and Fire/Ice, but Fish can't exactly be viewed as a real threat to win tournaments nowadays.
4 Coffin Purge
Planar Void
might be better... you've already got the Wretch for cards that make it to the graveyard before Void gets cast.
Engineered Plague-name goblin, merfolk, spirit, soldier, etc. just too, too good
More like too, too, slow, DZ. You're too concerned with creatures, and the piddly ones at that (other than the Welder, there isn't much out there at the top of Type I right now that will ever be affected by the Plague). At best (at best) this is a sideboard card if you plan on playing in a heavy budget meta. Trust me on this - I've actually
tried this card in Type I - way too slow, way too limited in scope.
For an investment of 3 mana, you could have a Negator out, putting your opponent on a 4-turn clock. Plague is too dependent on your opponent.
Chains of Mephistopheles-the hymn that keeps on working
I don't have any
personal experience with them, but I have a friend who has played Nether Void in Type I tournaments, and he maindecked them when Gro was in its prime. Even with the draw inherent in that archetype, he said that he still wished more often than not that the Chains would've been creature control - that said, Gro's creatures were better targets than somebody playing Meandeck Tendrils...
You may want to consider these as sideboard options only.
Speaking of which...
SB: 4 Sphere of Resistance/trinisphere-lets me go the psuedo void route
C'mon, man... Didn't you ever watch The Karate Kid...? "So-so" (or "pseudo) = "squish, just like grape."
Going "pseudo" in Type I is like saying "I haven't got a clear idea of what this deck should do, and I'm going to try to imitate the other decks out there, even though I don't have an entire deck to support these pieces..."
You have no mana acceleration that wouldn't be affected by your own Spheres (in effect, slowing
you down more than your opponents), making this a
terrible choice.
SB: 3 Masticore
Again with the weenie hate? You've got too many answers to something that isn't a real problem in Type I today...
The deck is obviusly focused towards antigraveyard and anti-welder. Those are the main decks in the format. Active Kiku helps against Oath, so does early duress.
Not to beat a dead horse, but this deck's only hope against Oath is an early Duress that doesn't get forced. Kiku blows. If the Oath comes into play, you die with this deck.
Graveyard recursion is Stax and Dragon...there are other decks in this format that don't rely on recursion (Oath, Tendrils, Mono-U, U/G Madness, Belcher to name a few). Did you mean those are the main decks in your metagame?
Have you ever read TMD's Legend Suicide primer? If you're going mono-black, that might be a good place to start.