Mentor of the Meek

Whenever another creature you control with power 2 or less enters, you may pay {1}. If you do, draw a card.

Thriving Heath

This land enters tapped. As it enters, choose a color other than white.
{T}: Add {W} or one mana of the chosen color.

Fortune, Loyal Steed

When Fortune enters, scry 2.
Whenever Fortune attacks while saddled, at end of combat, exile it and up to one creature that saddled it this turn, then return those cards to the battlefield under their owner's control.
Saddle 1

One Last Job

Spree (Choose one or more additional costs.)
+ {2} — Return target creature card from your graveyard to the battlefield.
+ {1} — Return target Mount or Vehicle card from your graveyard to the battlefield.
+ {1} — Return target Aura or Equipment card from your graveyard to the battlefield attached to a creature you control.

Spirited Companion

Plains

Trained Arynx

Whenever this creature attacks while saddled, it gains first strike until end of turn. Scry 1. (Look at the top card of your library. You may put that card on the bottom.)
Saddle 2 (Tap any number of other creatures you control with total power 2 or more: This Mount becomes saddled until end of turn. Saddle only as a sorcery.)

Shepherd of the Clouds

Flying, vigilance
When this creature enters, return target permanent card with mana value 3 or less from your graveyard to your hand. Return that card to the battlefield instead if you control a Mount.

Frontier Seeker

When this creature enters, look at the top five cards of your library. You may reveal a Mount creature card or a Plains card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.

Steer Clear

Steer Clear deals 2 damage to target attacking or blocking creature. Steer Clear deals 4 damage to that creature instead if you controlled a Mount as you cast this spell.

Bridled Bighorn

Vigilance
Whenever this creature attacks while saddled, create a 1/1 white Sheep creature token.
Saddle 2 (Tap any number of other creatures you control with total power 2 or more: This Mount becomes saddled until end of turn. Saddle only as a sorcery.)