Urborg, Tomb of Yawgmoth ?

I've been running a teysa deck as well, though more voltron then toekn. If you're working on lifegain, Rhox Faithmender is great. If you do grab an Urborg, Tomb of Yawgmoth , consider a Cabal Coffers or Magus of the Coffers . And if you want teysa to beat face, Eldrazi Conscription is a lot of fun

unlife I had faithmender in the first version of the deck, for obvious reasons, but decided against him because I already had so much lifelink, and while doubling it would be good, it didn't add to the spiral that is my main win condition. In that scenario, I only need to gain one life and the game is over.

I'll keep the other two cards in mind if I decide to get the tomb, but I'm not even sure I'll get that. I already had to fight so much to fit the cards in that I wanted, it would be a struggle to find two to cut

Fellwar Stone won't work as intended because of EDH rules. If you would produce an color mana outside the colors of your general it becomes colorless mana.

Electromancer Which is fine, it still boosts my mana count and the colourless can come in handy. In one on one I can see it being a drawback, but this is for playing with 3 or more people. I find that white and black are very versifier colours and an opponent will tend to have one of the colours I'd need