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.

Make Your Own Luck

Look at the top three cards of your library. You may exile a nonland card from among them. If you do, it becomes plotted. Put the rest into your hand. (You may cast it as a sorcery on a later turn without paying its mana cost.)

Map the Frontier

Search your library for up to two basic land cards and/or Desert cards, put them onto the battlefield tapped, then shuffle.

Jem Lightfoote, Sky Explorer

Flying, vigilance
At the beginning of your end step, if you haven't cast a spell from your hand this turn, draw a card.

Lassoed by the Law

When Lassoed by the Law enters, exile target nonland permanent an opponent controls until Lassoed by the Law leaves the battlefield.
When Lassoed by the Law enters, create a 1/1 red Mercenary creature token with "{T}: Target creature you control gets +1/+0 until end of turn. Activate only as a sorcery."

Metamorphic Blast

Spree (Choose one or more additional costs.)
+ {1} — Until end of turn, target creature becomes a white Rabbit with base power and toughness 0/1.
+ {3} — Target player draws two cards.

Kellan Joins Up

When Kellan Joins Up enters, you may exile a nonland card with mana value 3 or less from your hand. If you do, it becomes plotted. (You may cast it as a sorcery on a later turn without paying its mana cost.)
Whenever a legendary creature you control enters, put a +1/+1 counter on each creature you control.