Vicious Shadows

Whenever a creature dies, you may have Vicious Shadows deal damage to target player equal to the number of cards in that player's hand.

Connecting the Dots

Whenever a creature you control attacks, exile the top card of your library face down. (You can't look at it.)
{1}{R}, Discard your hand, Sacrifice Connecting the Dots: Put all cards exiled with Connecting the Dots into their owners' hands.

Head Games

Target opponent puts the cards from their hand on top of their library. Search that player's library for that many cards. The player puts those cards into their hand, then shuffles.

Mercadia's Downfall

Each attacking creature gets +1/+0 until end of turn for each nonbasic land defending player controls.

Lich's Mastery

Hexproof
You can't lose the game.
Whenever you gain life, draw that many cards.
Whenever you lose life, for each 1 life you lost, exile a permanent you control or a card from your hand or graveyard.
When Lich's Mastery leaves the battlefield, you lose the game.