Nykthos, Shrine to Nyx

{T}: Add {C}.
{2}, {T}: Choose a color. Add an amount of mana of that color equal to your devotion to that color. (Your devotion to a color is the number of mana symbols of that color in the mana costs of permanents you control.)

Utopia Sprawl

Enchant Forest
As Utopia Sprawl enters, choose a color.
Whenever enchanted Forest is tapped for mana, its controller adds an additional one mana of the chosen color.

Acidic Slime

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
When Acidic Slime enters, destroy target artifact, enchantment, or land.

Reclaiming Vines

Destroy target artifact, enchantment, or land.

Plow Under

Put two target lands on top of their owners' libraries.

Voyaging Satyr

Bramblecrush

Arbor Elf

Creeping Mold

Primal Command

Choose two —
• Target player gains 7 life.
• Put target noncreature permanent on top of its owner's library.
• Target player shuffles their graveyard into their library.
• Search your library for a creature card, reveal it, put it into your hand, then shuffle.

Mwonvuli Acid-Moss

Destroy target land. Search your library for a Forest card, put that card onto the battlefield tapped, then shuffle.

Eternal Witness

When Eternal Witness enters, you may return target card from your graveyard to your hand.

Forest

Stampeding Serow

Trample
At the beginning of your upkeep, return a green creature you control to its owner's hand.

Fertile Ground

Enchant land
Whenever enchanted land is tapped for mana, its controller adds an additional one mana of any color.