Kellan, the Kid

Flying, lifelink
Whenever you cast a spell from anywhere other than your hand, you may cast a permanent spell with equal or lesser mana value from your hand without paying its mana cost. If you don't, you may put a land card from your hand onto the battlefield.

Korlessa, Scale Singer

You may look at the top card of your library any time.
You may cast Dragon spells from the top of your library.

Ranger Class

(Gain the next level as a sorcery to add its ability.)
When Ranger Class enters, create a 2/2 green Wolf creature token.
{1}{G}: Level 2
Whenever you attack, put a +1/+1 counter on target attacking creature.
{3}{G}: Level 3
You may look at the top card of your library any time.
You may cast creature spells from the top of your library.

Fblthp, the Lost

When Fblthp enters, draw a card. If it entered from your library or was cast from your library, draw two cards instead.
When Fblthp becomes the target of a spell, shuffle Fblthp into its owner's library.

Betroth the Beast

Create a Royal Role token attached to target creature you control. (Enchanted creature gets +1/+1 and has ward {1}.)

Besotted Knight

Besotted Knight // Betroth the Beast

Errant and Giada

Flash
Flying
You may look at the top card of your library any time.
You may cast spells with flash or flying from the top of your library.

Gorion, Wise Mentor

Vigilance
Whenever you cast an Adventure spell, you may copy it. You may choose new targets for the copy.

Fblthp, Lost on the Range

Ward {2}
You may look at the top card of your library any time.
The top card of your library has plot. The plot cost is equal to its mana cost.
You may plot nonland cards from the top of your library.

Assemble the Players

You may look at the top card of your library any time.
Once each turn, you may cast a creature spell with power 2 or less from the top of your library.

Edgewall Innkeeper

Whenever you cast a creature spell that has an Adventure, draw a card. (It doesn't need to have gone on the adventure first.)

Storyteller Pixie

Flying
Whenever you cast an Adventure spell, draw a card.

Rob the Hoard

Return target artifact, enchantment, or legendary card from your graveyard to your hand. (Then exile this card. You may cast the creature later from exile.)

Crystal Dragon

Crystal Dragon // Rob the Hoard

Fertile Footsteps

Search your library for a basic land card, put it onto the battlefield, then shuffle. (Then exile this card. You may cast the creature later from exile.)

Beanstalk Giant

Beanstalk Giant's power and toughness are each equal to the number of lands you control.

Beanstalk Giant // Fertile Footsteps

Lucky Clover

Whenever you cast an Adventure instant or sorcery spell, copy it. You may choose new targets for the copy.