All lands are swamps with Urborg, Tomb of Yawgmoth.
All swamps are 1/1 creatures with Kormus bell.
All opponent creatures get -2/-2 from Elesh Norn, Grand Cenobite.
Each opponent lands can not be played.

When a land enters the battlefield, it becomes a Swamp due to Kormus Bell. This then causes it to become a 0/0 creature due to Urborg and Kaervek, and die as a state-based action due to having 0 toughness.

When a land enters the battlefield, it becomes a Swamp due to Kormus Bell. This then causes it to become a 0/0 creature due to Urborg and Night of Souls' Betrayal, and die as a state-based action due to having 0 toughness.

to cast it.

With Urborg on the battlefield, all lands are swamps.
With Kormus Bell on the battlefield, all Swamps are 1/1 creatures.
Cast Make Obsolete, giving all creatures your opponent control -1/-1 until end of turn, destroying all their lands.

Urborg turns all lands into Swamps.
Kormus Bell turns all swamps into creatures.
Linvala prevents your opponent' creatures from activating their abilities, including mana abilities.

Urborg and Kormus Bell cause all lands to be 1/1 creatures that are also Swamps in addition to their other types.
Because Drana and Linvala prevents your opponents from activating abilities of creatures they control, your opponents cannot activate abilities of lands or creatures they control.

Lands and creatures you control can tap to produce at least .

Activate all mana producing lands and creatures you control by tapping them, adding at least .
Activate Aggravated Assault by paying , untapping all creatures you control and getting an additional combat and main phase after this phase.
Repeat.

You control at least one additional nontoken creature.

Activate Phyrexian Altar by sacrificing another nontoken creature you control, adding one mana of any color.
When the creature dies, Yedora triggers, returning the creature from your graveyard to the battlefield face down as a Forest land and as a 1/1 Swamp creature due to Kormus Bell and Urborg.
Repeat.

You control at least one additional nontoken creature.

Activate Ashnod's Altar by sacrificing another nontoken creature you control, adding .
When the creature dies, Yedora triggers, returning the creature from your graveyard to the battlefield face down as a Forest land and as a 1/1 Swamp creature due to Kormus Bell and Urborg.
Repeat.

Viridian Longbow and Thornbite Staff attached to the same creature you control without summoning sickness.

Whenever a land enters the battlefield, it enters as a 1/1 creature due to Urborg and Kormus Bell.
Activate the creature with Viridian Longbow and Thornbite Staff attached by tapping it, dealing 1 damage to the land.
The land dies as a state-based action due to having zero toughness.
The creature triggers, untapping itself.
Repeat as desired for each land an opponent controls, and whenever a land enters the battlefield under an opponent's control.

Whenever a land enters the battlefield, it enters as a 1/1 Swamp creature due to Urborg and Kormus Bell.
Aether Flash triggers, dealing 2 damage to the land.
The land dies as a state-based action due to having less than zero toughness.

When a land enters the battlefield, it becomes a Swamp due to Kormus Bell. This then causes it to become a 0/0 creature due to Urborg and The Flesh Is Weak, and die as a state-based action due to having 0 toughness.