Dragonclaw Strike

Double the power and toughness of target creature you control until end of turn. Then it fights up to one target creature an opponent controls. (Each deals damage equal to its power to the other.)

Jori En, Ruin Diver

Whenever you cast your second spell each turn, draw a card.

Explore

You may play an additional land this turn.
Draw a card.

Kraum, Violent Cacophony

Flying
Whenever you cast your second spell each turn, put a +1/+1 counter on Kraum and draw a card.

Temur Ascendancy

Creatures you control have haste.
Whenever a creature you control with power 4 or greater enters, you may draw a card.

Temur Battlecrier

During your turn, spells you cast cost {1} less to cast for each creature you control with power 4 or greater.

Eshki Dragonclaw

Vigilance, trample, ward {1}
At the beginning of combat on your turn, if you've cast both a creature spell and a noncreature spell this turn, draw a card and put two +1/+1 counters on Eshki Dragonclaw.

Taigam, Master Opportunist

Flurry — Whenever you cast your second spell each turn, copy it, then exile the spell you cast with four time counters on it. If it doesn't have suspend, it gains suspend. (At the beginning of its owner's upkeep, they remove a time counter. When the last is removed, they may play it without paying its mana cost. If it's a creature, it has haste.)

Songcrafter Mage

Flash
When this creature enters, target instant or sorcery card in your graveyard gains harmonize until end of turn. Its harmonize cost is equal to its mana cost. (You may cast that card from your graveyard for its harmonize cost. You may tap a creature you control to reduce that cost by {X}, where X is its power. Then exile the spell.)