Ghalta, Primal Hunger

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

Snow-Covered Forest

Snow-Covered Swamp

Swift End

Destroy target creature or planeswalker. You lose 2 life. (Then exile this card. You may cast the creature later from exile.)

Murderous Rider

Lifelink
When Murderous Rider dies, put it on the bottom of its owner's library.

Murderous Rider // Swift End

Sultai Charm

Choose one —
• Destroy target monocolored creature.
• Destroy target artifact or enchantment.
• Draw two cards, then discard a card.

Snow-Covered Island

Malakir Cullblade

Whenever a creature an opponent controls dies, put a +1/+1 counter on Malakir Cullblade.

Phantom Ninja

Kraul Stinger

Sultai Ascendancy

At the beginning of your upkeep, surveil 2. (Look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)

Hired Poisoner

Stealth Mission

Put two +1/+1 counters on target creature you control. That creature can't be blocked this turn.

Rogue's Passage

{T}: Add {C}.
{4}, {T}: Target creature can't be blocked this turn.

Jace, Arcane Strategist

Whenever you draw your second card each turn, put a +1/+1 counter on target creature you control.
+1: Draw a card.
−7: Creatures you control can't be blocked this turn.

Binding the Old Gods

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Destroy target nonland permanent an opponent controls.
II — Search your library for a Forest card, put it onto the battlefield tapped, then shuffle.
III — Creatures you control gain deathtouch until end of turn.

Vraska the Unseen

+1: Until your next turn, whenever a creature deals combat damage to Vraska the Unseen, destroy that creature.
−3: Destroy target nonland permanent.
−7: Create three 1/1 black Assassin creature tokens with "Whenever this creature deals combat damage to a player, that player loses the game."

Baleful Eidolon

Bestow {4}{B} (If you cast this card for its bestow cost, it's an Aura spell with enchant creature. It becomes a creature again if it's not attached to a creature.)
Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
Enchanted creature gets +1/+1 and has deathtouch.