Gastal Thrillseeker

Start your engines! (If you have no speed, it starts at 1. It increases once on each of your turns when an opponent loses life. Max speed is 4.)
When this creature enters, it deals 1 damage to target opponent and you gain 1 life.
Max speed — This creature has deathtouch and haste.

Mountain

Swamp

Fanatical Firebrand

Haste (This creature can attack and {T} as soon as it comes under your control.)
{T}, Sacrifice this creature: It deals 1 damage to any target.

Eaten Alive

As an additional cost to cast this spell, sacrifice a creature or pay {3}{B}.
Exile target creature or planeswalker.

Viashino Pyromancer

When this creature enters, it deals 2 damage to target player or planeswalker.

Undying Malice

Until end of turn, target creature gains "When this creature dies, return it to the battlefield tapped under its owner's control with a +1/+1 counter on it."

Infestation Sage

When this creature dies, create a 1/1 black and green Insect creature token with flying.

Preacher of the Schism

Deathtouch
Whenever this creature attacks the player with the most life or tied for most life, create a 1/1 white Vampire creature token with lifelink.
Whenever this creature attacks while you have the most life or are tied for most life, you draw a card and you lose 1 life.

Inti, Seneschal of the Sun

Whenever you attack, you may discard a card. When you do, put a +1/+1 counter on target attacking creature. It gains trample until end of turn.
Whenever you discard one or more cards, exile the top card of your library. You may play that card until your next end step.

Zoyowa Lava-Tongue

Deathtouch
At the beginning of your end step, if you descended this turn, each opponent may discard a card or sacrifice a permanent of their choice. Zoyowa deals 3 damage to each opponent who didn't. (You descended if a permanent card was put into your graveyard from anywhere.)

Fear of Missing Out

When this creature enters, discard a card, then draw a card.
Delirium — Whenever this creature attacks for the first time each turn, if there are four or more card types among cards in your graveyard, untap target creature. After this phase, there is an additional combat phase.

Vampire Gourmand

Whenever this creature attacks, you may sacrifice another creature. If you do, draw a card and this creature can't be blocked this turn.

Sulfurous Springs

{T}: Add {C}.
{T}: Add {B} or {R}. This land deals 1 damage to you.

Deep-Cavern Bat

Flying, lifelink
When this creature enters, look at target opponent's hand. You may exile a nonland card from it until this creature leaves the battlefield.

Clockwork Percussionist

Haste
When this creature dies, exile the top card of your library. You may play it until the end of your next turn.

Go for the Throat

Blackcleave Cliffs

This land enters tapped unless you control two or fewer other lands.
{T}: Add {B} or {R}.

Insect

Immersturm Predator

Flying
Whenever this creature becomes tapped, exile up to one target card from a graveyard and put a +1/+1 counter on this creature.
Sacrifice another creature: This creature gains indestructible until end of turn. Tap it.

Vampire

Lifelink (Damage dealt by this creature also causes you to gain that much life.)

Burst Lightning

Kicker {4} (You may pay an additional {4} as you cast this spell.)
Burst Lightning deals 2 damage to any target. If this spell was kicked, it deals 4 damage instead.

Alesha, Who Laughs at Fate

First strike
Whenever Alesha attacks, put a +1/+1 counter on it.
Raid — At the beginning of your end step, if you attacked this turn, return target creature card with mana value less than or equal to Alesha's power from your graveyard to the battlefield.

Braids, Arisen Nightmare

At the beginning of your end step, you may sacrifice an artifact, creature, enchantment, land, or planeswalker. If you do, each opponent may sacrifice a permanent of their choice that shares a card type with it. For each opponent who doesn't, that player loses 2 life and you draw a card.

Snarling Gorehound

Menace
Whenever another creature you control with power 2 or less enters, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)

Perforating Artist

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
Raid — At the beginning of your end step, if you attacked this turn, each opponent loses 3 life unless that player sacrifices a nonland permanent of their choice or discards a card.

Have

Getting

Don't Have

Burn

Sacrifice

Budget

{"ops":[{"insert":"mostly borrowed from a post by u/MonoMountains in r/spikes\n"}]}