Lord of Extinction

Lord of Extinction's power and toughness are each equal to the number of cards in all graveyards.

Hydromorph Gull

Flying
{U}, Sacrifice this creature: Counter target spell that targets a creature you control.

Phyrexian Arena

At the beginning of your upkeep, you draw a card and you lose 1 life.

Beza, the Bounding Spring

When Beza enters, create a Treasure token if an opponent controls more lands than you. You gain 4 life if an opponent has more life than you. Create two 1/1 blue Fish creature tokens if an opponent controls more creatures than you. Draw a card if an opponent has more cards in hand than you.

Rumbleweed

This spell costs {1} less to cast for each land card in your graveyard.
Vigilance, reach, trample
When this creature enters, other creatures you control get +3/+3 and gain trample until end of turn.

Shroudstomper

Deathtouch
Whenever this creature enters or attacks, each opponent loses 2 life. You gain 2 life and draw a card.

Hydromorph Guardian

{U}, Sacrifice this creature: Counter target spell that targets a creature you control.

Relic of Legends

{T}: Add one mana of any color.
Tap an untapped legendary creature you control: Add one mana of any color.

Earth-Cult Elemental

Siege Monster — When this creature enters, roll a d20.
1—9 | Each player sacrifices a permanent of their choice.
10—19 | Each opponent sacrifices a permanent of their choice.
20 | Each opponent sacrifices two permanents of their choice.

Flickerwisp

Flying
When this creature enters, exile another target permanent. Return that card to the battlefield under its owner's control at the beginning of the next end step.

Rottenmouth Viper

As an additional cost to cast this spell, you may sacrifice any number of nonland permanents. This spell costs {1} less to cast for each permanent sacrificed this way.
Whenever this creature enters or attacks, put a blight counter on it. Then for each blight counter on it, each opponent loses 4 life unless that player sacrifices a nonland permanent of their choice or discards a card.

Command Tower

{T}: Add one mana of any color in your commander's color identity.

Titan of Industry

Reach, trample
When this creature enters, choose two —
• Destroy target artifact or enchantment.
• Target player gains 5 life.
• Create a 4/4 green Rhino Warrior creature token.
• Put a shield counter on a creature you control.

Cavalier of Flame

{1}{R}: Creatures you control get +1/+0 and gain haste until end of turn.
When this creature enters, discard any number of cards, then draw that many cards.
When this creature dies, it deals X damage to each opponent and each planeswalker they control, where X is the number of land cards in your graveyard.

Horde of Notions

Vigilance, trample, haste
{W}{U}{B}{R}{G}: You may play target Elemental card from your graveyard without paying its mana cost.

Bane of Progress

When this creature enters, destroy all artifacts and enchantments. Put a +1/+1 counter on this creature for each permanent destroyed this way.

Quicksilver Elemental

{U}: This creature gains all activated abilities of target creature until end of turn. (If any of the abilities use that creature's name, use this creature's name instead.)
You may spend blue mana as though it were mana of any color to pay the activation costs of this creature's abilities.

Nyxbloom Ancient

Trample
If you tap a permanent for mana, it produces three times as much of that mana instead.

Mulldrifter

Flying
When this creature enters, draw two cards.
Evoke {2}{U} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters.)