Ghalta, Primal Hunger

This spell costs {X} less to cast, where X is the total power of creatures you control.
Trample

Etali, Primal Storm

Whenever Etali, Primal Storm attacks, exile the top card of each player's library, then you may cast any number of spells from among those cards without paying their mana costs.

Giada, Font of Hope

Flying, vigilance
Each other Angel you control enters with an additional +1/+1 counter on it for each Angel you already control.
{T}: Add {W}. Spend this mana only to cast an Angel spell.

Brisela, Voice of Nightmares

Flying, first strike, vigilance, lifelink
Your opponents can't cast spells with mana value 3 or less.

Cursed Courtier

Lifelink
When Cursed Courtier enters, create a Cursed Role token attached to it. (Enchanted creature is 1/1.)

Near-Death Experience

At the beginning of your upkeep, if you have exactly 1 life, you win the game.

Don Andres, the Renegade

Each creature you control but don't own gets +2/+2, has menace and deathtouch, and is a Pirate in addition to its other types.
Whenever you cast a noncreature spell you don't own, create two tapped Treasure tokens.