Geothermal Bog

({T}: Add {B} or {R}.)
Geothermal Bog enters tapped.

Dread Return

Return target creature card from your graveyard to the battlefield.
Flashback—Sacrifice three creatures. (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Demonic Dread

Cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order.)
Target creature can't block this turn.

Mountain

Simian Spirit Guide

Exile Simian Spirit Guide from your hand: Add {R}.

Ingot Chewer

When Ingot Chewer enters, destroy target artifact.
Evoke {R} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters.)

Forest

Mine Collapse

If it's your turn, you may sacrifice a Mountain rather than pay this spell's mana cost.
Mine Collapse deals 5 damage to target creature or planeswalker.

Violent Outburst

Cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order.)
Creatures you control get +1/+0 until end of turn.

Oliphaunt

Trample
Whenever Oliphaunt attacks, another target creature you control gets +2/+0 and gains trample until end of turn.
Mountaincycling {1} ({1}, Discard this card: Search your library for a Mountain card, reveal it, put it into your hand, then shuffle.)

Spinning Darkness

You may exile the top three black cards of your graveyard rather than pay this spell's mana cost.
Spinning Darkness deals 3 damage to target nonblack creature. You gain 3 life.

Generous Ent

Reach
When Generous Ent enters, create a Food token. (It's an artifact with "{2}, {T}, Sacrifice this artifact: You gain 3 life.")
Forestcycling {1} ({1}, Discard this card: Search your library for a Forest card, reveal it, put it into your hand, then shuffle.)

Drown in Sorrow

All creatures get -2/-2 until end of turn. Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Haunted Mire

({T}: Add {B} or {G}.)
Haunted Mire enters tapped.

Wooded Ridgeline

({T}: Add {R} or {G}.)
Wooded Ridgeline enters tapped.

Faerie Macabre

Flying
Discard Faerie Macabre: Exile up to two target cards from graveyards.

Exhume

Each player puts a creature card from their graveyard onto the battlefield.

Gloomfang Mauler

Swampcycling {2} ({2}, Discard this card: Search your library for a Swamp card, reveal it, put it into your hand, then shuffle.)
Backup 2 (When this creature enters, put two +1/+1 counters on target creature. If that's another creature, it gains the following ability until end of turn.)
Menace

Troll of Khazad-dûm

Troll of Khazad-dûm can't be blocked except by three or more creatures.
Swampcycling {1} ({1}, Discard this card: Search your library for a Swamp card, reveal it, put it into your hand, then shuffle.)

Swamp

Bojuka Bog

Bojuka Bog enters tapped.
When Bojuka Bog enters, exile target player's graveyard.
{T}: Add {B}.

Gone

Return target creature you don't control to its owner's hand.

Dead

Dead // Gone

Reverent Silence

If you control a Forest, rather than pay this spell's mana cost, you may have each other player gain 6 life.
Destroy all enchantments.

Snuff Out

If you control a Swamp, you may pay 4 life rather than pay this spell's mana cost.
Destroy target nonblack creature. It can't be regenerated.