Teferi's Puzzle Box

At the beginning of each player's draw step, that player puts the cards in their hand on the bottom of their library in any order, then draws that many cards.

Cavalier of Flame

{1}{R}: Creatures you control get +1/+0 and gain haste until end of turn.
When Cavalier of Flame enters, discard any number of cards, then draw that many cards.
When Cavalier of Flame dies, it deals X damage to each opponent and each planeswalker they control, where X is the number of land cards in your graveyard.