Possibility Technician

Whenever this creature or another Kavu you control enters, exile the top card of your library. For as long as that card remains exiled, you may play it if you control a Kavu.
Warp {1}{R} (You may cast this card from your hand for its warp cost. Exile this creature at the beginning of the next end step, then you may cast it from exile on a later turn.)

Plargg and Nassari

At the beginning of your upkeep, each player exiles cards from the top of their library until they exile a nonland card. An opponent chooses a nonland card exiled this way. You may cast up to two spells from among the other cards exiled this way without paying their mana costs.

Defiler of Instinct

First strike
As an additional cost to cast red permanent spells, you may pay 2 life. Those spells cost {R} less to cast if you paid life this way. This effect reduces only the amount of red mana you pay.
Whenever you cast a red permanent spell, this creature deals 1 damage to any target.

Tannuk, Steadfast Second

Other creatures you control have haste.
Artifact cards and red creature cards in your hand have warp {2}{R}. (You may cast a card from your hand for its warp cost. Exile that permanent at the beginning of the next end step, then you may cast it from exile on a later turn.)

Passionate Archaeologist

Commander creatures you own have "Whenever you cast a spell from exile, this creature deals damage equal to that spell's mana value to target opponent."

Tavern Brawler

Commander creatures you own have "At the beginning of your upkeep, exile the top card of your library. This creature gets +X/+0 until end of turn, where X is that card's mana value. You may play that card this turn."

Trumpeting Carnosaur

Trample
When this creature enters, discover 5.
{2}{R}, Discard this card: It deals 3 damage to target creature or planeswalker.