Tyvar the Bellicose

Whenever one or more Elves you control attack, they gain deathtouch until end of turn.
Each creature you control has "Whenever a mana ability of this creature resolves, put a number of +1/+1 counters on it equal to the amount of mana this creature produced. This ability triggers only once each turn."

Blinkmoth Nexus

{T}: Add {C}.
{1}: This land becomes a 1/1 Blinkmoth artifact creature with flying until end of turn. It's still a land.
{1}, {T}: Target Blinkmoth creature gets +1/+1 until end of turn.

Dread Statuary

{T}: Add {C}.
{4}: This land becomes a 4/2 Golem artifact creature until end of turn. It's still a land.

Spawning Pool

This land enters tapped.
{T}: Add {B}.
{1}{B}: This land becomes a 1/1 black Skeleton creature with "{B}: Regenerate this creature" until end of turn. It's still a land. (If it regenerates, the next time it would be destroyed this turn, instead tap it, remove it from combat, and heal all damage on it.)

Forest

Hissing Quagmire

This land enters tapped.
{T}: Add {B} or {G}.
{1}{B}{G}: This land becomes a 2/2 black and green Elemental creature with deathtouch until end of turn. It's still a land.

Svogthos, the Restless Tomb

{T}: Add {C}.
{3}{B}{G}: Until end of turn, this land becomes a black and green Plant Zombie creature with "This creature's power and toughness are each equal to the number of creature cards in your graveyard." It's still a land.

Kami of Whispered Hopes

If one or more +1/+1 counters would be put on a permanent you control, that many plus one +1/+1 counters are put on that permanent instead.
{T}: Add X mana of any one color, where X is this creature's power.

Scavenger Grounds

{T}: Add {C}.
{2}, {T}, Sacrifice a Desert: Exile all graveyards.

Mishra's Factory

{T}: Add {C}.
{1}: This land becomes a 2/2 Assembly-Worker artifact creature until end of turn. It's still a land.
{T}: Target Assembly-Worker creature gets +1/+1 until end of turn.

Swamp

Restless Cottage

This land enters tapped.
{T}: Add {B} or {G}.
{2}{B}{G}: This land becomes a 4/4 black and green Horror creature until end of turn. It's still a land.
Whenever this land attacks, create a Food token and exile up to one target card from a graveyard.

Treetop Village

This land enters tapped.
{T}: Add {G}.
{1}{G}: This land becomes a 3/3 green Ape creature with trample until end of turn. It's still a land. (It can deal excess combat damage to the player or planeswalker it's attacking.)

Demolition Field

{T}: Add {C}.
{2}, {T}, Sacrifice this land: Destroy target nonbasic land an opponent controls. That land's controller may search their library for a basic land card, put it onto the battlefield, then shuffle. You may search your library for a basic land card, put it onto the battlefield, then shuffle.