Emergence Zone

{T}: Add {C}.
{1}, {T}, Sacrifice Emergence Zone: You may cast spells this turn as though they had flash.

Sol Ring

Thrumming Stone

Spells you cast have ripple 4. (Whenever you cast a spell, you may reveal the top four cards of your library. You may cast spells with the same name as that spell from among the revealed cards without paying their mana costs. Put the rest on the bottom of your library.)

Fortuitous Find

Choose one or both —
• Return target artifact card from your graveyard to your hand.
• Return target creature card from your graveyard to your hand.

Relentless Rats

Relentless Rats gets +1/+1 for each other creature on the battlefield named Relentless Rats.
A deck can have any number of cards named Relentless Rats.

Culling the Weak

As an additional cost to cast this spell, sacrifice a creature.
Add {B}{B}{B}{B}.

Maralen of the Mornsong

Players can't draw cards.
At the beginning of each player's draw step, that player loses 3 life, searches their library for a card, puts it into their hand, then shuffles.

Dash Hopes

When you cast this spell, any player may pay 5 life. If a player does, counter Dash Hopes.
Counter target spell.

Swamp

Withering Boon

As an additional cost to cast this spell, pay 3 life.
Counter target creature spell.

Blood Pet

Piper of the Swarm

Rats you control have menace.
{1}{B}, {T}: Create a 1/1 black Rat creature token.
{2}{B}{B}, {T}, Sacrifice three Rats: Gain control of target creature.