@ Damnosus

18 Swamp, if you're playing 4 Dark Ritual and running the Confidant build (lots of 1-2cc spells, 4-8 3cc spells), is fine. I've never come across 18 Swamp being too low. I think Tacosnape, when he played Sui Black, also came to the conclusion that 18 Swamp + 4 Dark Ritual is sufficient for Confidant Sui.

EDIT: For reference

18 Swamp
4 Dark Ritual

4 Phyrexian Negator
4 Hypnotic Specter
4 Nantuko Shade
4 Stromgald Crusader
4 Dark Confidant

4 Duress
4 Thoughtseize
4 Hymn to Tourach
4 Smother
2 Umezawa's Jitte

SB:

4 Leyline of the Void
4 Engineered Plague
4 Dystopia
3 Pithing Needle

Pretty standard Confidant Sui. I'd like my chances versus Team America with this list; Stifle, Wasteland, Snuff Out are all dead (I suppose Stifle can be pitched to FoW, but whatever), our disruption suite is comparable, we both run legit clocks (theirs being largely dependant on the yard though), Confidant vs. their dig is somewhat comparable, and Dark Ritual can help against their Sinkholes.