Muraganda Raceway

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.)
{T}: Add {C}.
Max speed — {T}: Add {C}{C}.

Hour of Victory

Start your engines!
When this enchantment enters, create a 2/2 black Zombie creature token.
Max speed — {1}{B}, Sacrifice this enchantment: Search your library for a card, put it into your hand, then shuffle. Activate only as a sorcery.

The Speed Demon

Flying, trample
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.)
At the beginning of your end step, you draw X cards and lose X life, where X is your speed.

Goblin Surveyor

Trample
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.)
Max speed — {3}, Exile this card from your graveyard: Draw a card.

Avishkar Raceway

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.)
{T}: Add {C}.
Max speed — {3}, {T}, Discard a card: Draw a card.

Starting Column

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.)
{T}: Add one mana of any color.
Max speed — {T}, Sacrifice this artifact: Draw two cards, then discard a card.

Far Fortune, End Boss

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.)
Whenever you attack, Far Fortune deals 1 damage to each opponent.
Max speed — If a source you control would deal damage to an opponent or a permanent an opponent controls, it deals that much damage plus 1 instead.

Risen Necroregent

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.)
Max speed — At the beginning of your end step, create a 2/2 black Zombie creature token.

Hazoret, Godseeker

Indestructible, haste
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.)
{1}, {T}: Target creature with power 2 or less can't be blocked this turn.
Hazoret can't attack or block unless you have max speed.

Howlsquad Heavy

Start your engines!
Other Goblins you control have haste.
At the beginning of combat on your turn, create a 1/1 red Goblin creature token. That token attacks this combat if able.
Max speed — {T}: Add {R} for each Goblin you control.

Walking Sarcophagus

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.)
Max speed — This creature gets +1/+2.

Amonkhet Raceway

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.)
{T}: Add {C}.
Max speed — {T}: Target creature gains haste until end of turn.

Gas Guzzler

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.)
This creature enters tapped.
Max speed — {B}, Sacrifice another creature or Vehicle: Draw a card.

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.

Endrider Spikespitter

Reach
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.)
Max speed — At the beginning of your upkeep, exile the top card of your library. You may play that card this turn.

Kickoff Celebrations

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 enchantment enters, you may discard a card. If you do, draw two cards.
Max speed — Sacrifice this enchantment: Creatures and Vehicles you control gain haste until end of turn.

Mutant Surveyor

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.)
{2}: This creature gets +1/+1 until end of turn.
Max speed — {3}, Exile this card from your graveyard: Draw a card.

Endrider Catalyzer

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.)
Max speed — {T}: Add {R}{R}.