Shorikai, Genesis Engine

{1}, {T}: Draw two cards, then discard a card. Create a 1/1 colorless Pilot creature token with "This token crews Vehicles as though its power were 2 greater."
Crew 8 (Tap any number of creatures you control with total power 8 or more: This Vehicle becomes an artifact creature until end of turn.)
Shorikai, Genesis Engine can be your commander.

Mobilizer Mech

Flying
Whenever this Vehicle becomes crewed, up to one other target Vehicle you control becomes an artifact creature until end of turn.
Crew 3 (Tap any number of creatures you control with total power 3 or more: This Vehicle becomes an artifact creature until end of turn.)

Mechtitan Core

{5}, Exile this Vehicle and four other artifact creatures and/or Vehicles you control: Create Mechtitan, a legendary 10/10 Construct artifact creature token with flying, vigilance, trample, lifelink, and haste that's all colors. When that token leaves the battlefield, return all cards exiled with this Vehicle except this card to the battlefield tapped under their owners' control.
Crew 2

Skysovereign, Consul Flagship

Flying
Whenever Skysovereign enters or attacks, it deals 3 damage to target creature or planeswalker an opponent controls.
Crew 3 (Tap any number of creatures you control with total power 3 or more: This Vehicle becomes an artifact creature until end of turn.)

Thran Dynamo

Born to Drive

Enchant artifact or creature
As long as enchanted permanent is a creature, it gets +1/+1 for each creature and/or Vehicle you control.
Channel — {2}{W}, Discard this card: Create two 1/1 colorless Pilot creature tokens with "This token crews Vehicles as though its power were 2 greater."

Peacewalker Colossus

{1}{W}: Another target Vehicle you control becomes an artifact creature until end of turn.
Crew 4 (Tap any number of creatures you control with total power 4 or more: This Vehicle becomes an artifact creature until end of turn.)

Sol Ring

Fabricate

Search your library for an artifact card, reveal it, put it into your hand, then shuffle.

Enlightened Tutor

Search your library for an artifact or enchantment card, reveal it, then shuffle and put that card on top.

Nautiloid Ship

Flying
When this Vehicle enters, exile target player's graveyard.
Whenever this Vehicle deals combat damage to a player, you may put a creature card exiled with this Vehicle onto the battlefield under your control.
Crew 3

Swift Reconfiguration

Flash
Enchant creature or Vehicle
Enchanted permanent is a Vehicle artifact with crew 5 and it loses all other card types. (It's not a creature unless it's crewed.)

Colossal Plow

Whenever this Vehicle attacks, add {W}{W}{W} and you gain 3 life. Until end of turn, you don't lose this mana as steps and phases end.
Crew 6 (Tap any number of creatures you control with total power 6 or more: This Vehicle becomes an artifact creature until end of turn.)

Surgehacker Mech

Menace
When this Vehicle enters, it deals damage equal to twice the number of Vehicles you control to target creature or planeswalker an opponent controls.
Crew 4

Kotori, Pilot Prodigy

Vehicles you control have crew 2.
At the beginning of combat on your turn, target artifact creature you control gains lifelink and vigilance until end of turn.

Imposter Mech

You may have this Vehicle enter as a copy of a creature an opponent controls, except it's a Vehicle artifact with crew 3 and it loses all other card types.
Crew 3

Mystical Tutor

Search your library for an instant or sorcery card, reveal it, then shuffle and put that card on top.

Prodigy's Prototype

Whenever one or more Vehicles you control attack, create a 1/1 colorless Pilot creature token with "This token crews Vehicles as though its power were 2 greater."
Crew 2 (Tap any number of creatures you control with total power 2 or more: This Vehicle becomes an artifact creature until end of turn.)

Parhelion II

Flying, first strike, vigilance
Whenever Parhelion II attacks, create two 4/4 white Angel creature tokens with flying and vigilance that are attacking.
Crew 4 (Tap any number of creatures you control with total power 4 or more: This Vehicle becomes an artifact creature until end of turn.)