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.

Command Tower

{T}: Add one mana of any color in your commander's color identity.

Point the Way

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.)
{3}{G}, Sacrifice this enchantment: Search your library for up to X basic land cards, where X is your speed. Put those cards onto the battlefield tapped, then shuffle.

Forest

Lightwheel Enhancements

Enchant creature or Vehicle
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.)
Enchanted permanent gets +1/+1 and has vigilance.
Max speed — You may cast this card from your graveyard.

Warleader's Call

Creatures you control get +1/+1.
Whenever a creature you control enters, this enchantment deals 1 damage to each opponent.

Impact Tremors

Whenever a creature you control enters, this enchantment deals 1 damage to each opponent.

Plains

Mountain

Path of Ancestry

This land enters tapped.
{T}: Add one mana of any color in your commander's color identity. When that mana is spent to cast a creature spell that shares a creature type with your commander, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Garruk's Uprising

When this enchantment enters, if you control a creature with power 4 or greater, draw a card.
Creatures you control have trample. (Each of those creatures can deal excess combat damage to the player or planeswalker it's attacking.)
Whenever a creature you control with power 4 or greater enters, draw a card.