Seraphic Steed

First strike, lifelink
Whenever this creature attacks while saddled, create a 3/3 white Angel creature token with flying.
Saddle 4 (Tap any number of other creatures you control with total power 4 or more: This Mount becomes saddled until end of turn. Saddle only as a sorcery.)

Defend the Rider

Choose one —
• Target permanent you control gains hexproof and indestructible until end of turn.
• Create a 1/1 colorless Pilot creature token with "This token saddles Mounts and crews Vehicles as though its power were 2 greater."

Gloryheath Lynx

Lifelink
Whenever this creature attacks while saddled, search your library for a basic Plains card, reveal it, put it into your hand, then shuffle.
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.)

The Aetherspark

As long as The Aetherspark is attached to a creature, The Aetherspark can't be attacked and has "Whenever equipped creature deals combat damage during your turn, put that many loyalty counters on The Aetherspark."
+1: Attach The Aetherspark to up to one target creature you control. Put a +1/+1 counter on that creature.
−5: Draw two cards.
−10: Add ten mana of any one color.

Miriam, Herd Whisperer

During your turn, Mounts and Vehicles you control have hexproof.
Whenever a Mount or Vehicle you control attacks, put a +1/+1 counter on it.

Veteran Beastrider

At the beginning of your end step, untap each creature you control.
{2}{G}{W}: Creatures you control get +1/+1 until end of turn.

Lagorin, Soul of Alacria

Flying
Whenever Lagorin attacks while saddled, put a +1/+1 counter on each of up to two target Mounts and/or Vehicles.
Saddle 1 (Tap any number of other creatures you control with total power 1 or more: This Mount becomes saddled until end of turn. Saddle only as a sorcery.)

Wylie Duke, Atiin Hero

Vigilance
Whenever Wylie Duke becomes tapped, you gain 1 life and draw a card.

Interface Ace

This creature saddles Mounts and crews Vehicles using its toughness rather than its power.
Whenever this creature becomes tapped during your turn, untap it. This ability triggers only once each turn.

Drover Grizzly

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

Giant Beaver

Vigilance
Whenever this creature attacks while saddled, put a +1/+1 counter on target creature that saddled it this turn.
Saddle 3 (Tap any number of other creatures you control with total power 3 or more: This Mount becomes saddled until end of turn. Saddle only as a sorcery.)

Caradora, Heart of Alacria

When Caradora enters, you may search your library for a Mount or Vehicle card, reveal it, put it into your hand, then shuffle.
If one or more +1/+1 counters would be put on a creature or Vehicle you control, that many plus one +1/+1 counters are put on it instead.

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

Bounding Felidar

Whenever this creature attacks while saddled, put a +1/+1 counter on each other creature you control. You gain 1 life for each of those creatures.
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.)

Canyon Vaulter

Whenever this creature saddles a Mount or crews a Vehicle during your main phase, that Mount or Vehicle gains flying until end of turn.

Guardian Sunmare

Ward {2}
Whenever this creature attacks while saddled, search your library for a nonland permanent card with mana value 3 or less, put it onto the battlefield, then shuffle.
Saddle 4

Congregation Gryff

Flying, lifelink
Whenever this creature attacks while saddled, it gets +X/+X until end of turn, where X is the number of Mounts you control.
Saddle 3 (Tap any number of other creatures you control with total power 3 or more: This Mount becomes saddled until end of turn. Saddle only as a sorcery.)

Roadside Assistance

Enchant creature or Vehicle
When this Aura enters, create a 1/1 colorless Pilot creature token with "This token saddles Mounts and crews Vehicles as though its power were 2 greater."
Enchanted permanent gets +1/+1 and has lifelink.

Unswerving Sloth

Whenever this creature attacks while saddled, it gains indestructible until end of turn. Untap all creatures you control.
Saddle 4 (Tap any number of other creatures you control with total power 4 or more: This Mount becomes saddled until end of turn. Saddle only as a sorcery.)

Venomsac Lagac

Deathtouch
Whenever this creature attacks while saddled, it gets +0/+3 until end of turn.
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.)

District Mascot

This creature enters with a +1/+1 counter on it.
{1}{G}, Remove two +1/+1 counters from this creature: Destroy target artifact.
Whenever this creature attacks while saddled, put a +1/+1 counter on it.
Saddle 1

Autarch Mammoth

When this creature enters and whenever it attacks while saddled, create a 3/3 green Elephant creature token.
Saddle 5 (Tap any number of other creatures you control with total power 5 or more: This Mount becomes saddled until end of turn. Saddle only as a sorcery.)

Cloudspire Captain

Mounts and Vehicles you control get +1/+1.
This creature saddles Mounts and crews Vehicles as though its power were 2 greater.

Ornery Tumblewagg

At the beginning of combat on your turn, put a +1/+1 counter on target creature.
Whenever this creature attacks while saddled, double the number of +1/+1 counters on target creature.
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.)