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}.

Runaway Boulder

Flash
When this artifact enters, it deals 6 damage to target creature an opponent controls.
Cycling {2} ({2}, Discard this card: Draw a card.)

Speedway Fanatic

Haste
Whenever this creature crews a Vehicle, that Vehicle gains haste until end of turn.

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.

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.

Racers' Scoreboard

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 artifact enters, draw two cards, then discard a card.
Max speed — Spells you cast cost {1} less to cast.

Run Aground

Put target artifact or creature on top of its owner's library.

Anger

Haste
As long as this card is in your graveyard and you control a Mountain, creatures you control have haste.

Sonic the Hedgehog

Haste
Gotta Go Fast — Whenever Sonic the Hedgehog attacks, put a +1/+1 counter on each creature you control with flash or haste.
Whenever a creature you control with flash or haste is dealt damage, create a tapped Treasure token.

Arc Runner

Haste (This creature can attack and {T} as soon as it comes under your control.)
At the beginning of the end step, sacrifice this creature.

Racecourse Fury

Enchant land
Enchanted land has "{T}: Target creature gains haste until end of turn."