Kolodin, Triumph Caster

Mounts and Vehicles you control have haste.
Whenever a Mount you control enters, it becomes saddled until end of turn.
Whenever a Vehicle you control enters, it becomes an artifact creature until end of turn.

Samut, the Driving Force

First strike, vigilance, 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.)
Other creatures you control get +X/+0, where X is your speed.
Noncreature spells you cast cost {X} less to cast, where X is your speed.

Burnout Bashtronaut

Menace
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/+0 until end of turn.
Max speed — This creature has double strike.

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.

Lumbering Worldwagon

This Vehicle's power is equal to the number of lands you control.
Whenever this Vehicle enters or attacks, you may search your library for a basic land card, put it onto the battlefield tapped, then shuffle.
Crew 4