A typical game plan for white
Even in the 99 of a Landfall deck, Omnath will do a ton of work and represent a must-kill threat, lest it provide an "army in a can" and take over a game by itself
Giving it to them forever, of course
(2018-01-19) If you also control Yet Another Aether Vortex, any of the four revealed cards that are permanent cards will also be on the battlefield
Every dual land comes with a cost or trade-off: Life payments Shock Lands cost 2 life, Pain Lands cost 1 life per colored mana Tempo loss Tapped entries delay plays by one turn Deck construction requirements Check Lands need typed lands, Tango Lands need basics Conditional reliability Fast Lands fail late game, Battlebond Lands fail in 1v1 To choose the right balance, make sure to consider the format, deck speed, and overall strategy
As Commander games can often become all about the commander themselves, the ability to save some commander tax for the price of one instance of commander tax is pretty solid