Breath Weapon

Breath Weapon deals 2 damage to each non-Dragon creature.

Have

Oliphaunt

Trample
Whenever this creature 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.)

Cast into the Fire

Choose one —
• Cast into the Fire deals 1 damage to each of up to two target creatures.
• Exile target artifact.

Weather the Storm

You gain 3 life.
Storm (When you cast this spell, copy it for each spell cast before it this turn.)

Writhing Chrysalis

Devoid (This card has no color.)
When you cast this spell, create two 0/1 colorless Eldrazi Spawn creature tokens with "Sacrifice this token: Add {C}."
Reach
Whenever you sacrifice another Eldrazi, put a +1/+1 counter on this creature.

Arbor Elf

Eldrazi Spawn

Food

{2}, {T}, Sacrifice this token: You gain 3 life.

The Initiative

Whenever one or more creatures a player controls deal combat damage to you, that player takes the initiative.
Whenever you take the initiative and at the beginning of your upkeep, venture into Undercity. (If you're in a dungeon, advance to the next room. If you're not, enter Undercity. You can take the initiative even if you already have it.)

Undercity

You can't enter this dungeon unless you "venture into Undercity."
Secret Entrance — Search your library for a basic land card, reveal it, put it into your hand, then shuffle. (Leads to: Forge, Lost Well)
Forge — Put two +1/+1 counters on target creature. (Leads to: Trap!, Arena)
Lost Well — Scry 2. (Leads to: Arena, Stash)
Trap! — Target player loses 5 life. (Leads to: Archives)
Arena — Goad target creature. (Leads to: Archives, Catacombs)
Stash — Create a Treasure token. (Leads to: Catacombs)
Archives — Draw a card. (Leads to: Throne of the Dead Three)
Catacombs — Create a 4/1 black Skeleton creature token with menace. (Leads to: Throne of the Dead Three)
Throne of the Dead Three — Reveal the top ten cards of your library. Put a creature card from among them onto the battlefield with three +1/+1 counters on it. It gains hexproof until your next turn. Then shuffle.

Undercity // The Initiative

Annoyed Altisaur

Reach, trample
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.)

Malevolent Rumble

Reveal the top four cards of your library. You may put a permanent card from among them into your hand. Put the rest into your graveyard. Create a 0/1 colorless Eldrazi Spawn creature token with "Sacrifice this token: Add {C}."

Eldrazi Repurposer

Devoid (This card has no color.)
When you cast this spell and when this creature dies, create a 0/1 colorless Eldrazi Spawn creature token with "Sacrifice this token: Add {C}."

Generous Ent

Reach
When this creature enters, create a Food token. (It's an artifact with "{2}, {T}, Sacrifice this token: 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.)

Relic of Progenitus

{T}: Target player exiles a card from their graveyard.
{1}, Exile this artifact: Exile all graveyards. Draw a card.

Utopia Sprawl

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

Nyxborn Hydra

Bestow {X}{G}{G} (If you cast this card for its bestow cost, it's an Aura spell with enchant creature. It becomes a creature again if it's not attached.)
Reach, trample
This permanent enters with X +1/+1 counters on it.
Enchanted creature gets +1/+1 for each +1/+1 counter on this Aura and has reach and trample.

Gorilla Shaman

{X}{X}{1}: Destroy target noncreature artifact with mana value X.

Deglamer

Choose target artifact or enchantment. Its owner shuffles it into their library.

Boarding Party

Haste
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.)

You Meet in a Tavern

Choose one —
• Form a Party — Look at the top five cards of your library. You may reveal any number of creature cards from among them and put them into your hand. Put the rest on the bottom of your library in a random order.
• Start a Brawl — Creatures you control get +2/+2 until end of turn.

Avenging Hunter

Trample
When this creature enters, you take the initiative.

Mountain

Wooded Ridgeline

({T}: Add {R} or {G}.)
This land enters tapped.

Forest

Wild Growth

Enchant land
Whenever enchanted land is tapped for mana, its controller adds an additional {G}.