Blighted Agent

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
This creature can't be blocked.

Spell Pierce

Counter target noncreature spell unless its controller pays {2}.

Plague Stinger

Flying
Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Open the Gates

Search your library for a basic land card or Gate card, reveal it, put it into your hand, then shuffle.

Might of Old Krosa

Target creature gets +2/+2 until end of turn. If you cast this spell during your main phase, that creature gets +4/+4 until end of turn instead.

Experimental Augury

Look at the top three cards of your library. Put one of them into your hand and the rest on the bottom of your library in any order. Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Dispel

Turn Inside Out

Target creature gets +3/+0 until end of turn. When it dies this turn, manifest dread. (Look at the top two cards of your library. Put one onto the battlefield face down as a 2/2 creature and the other into your graveyard. Turn it face up any time for its mana cost if it's a creature card.)

Cliffgate

This land enters tapped.
As this land enters, choose a color other than red.
{T}: Add {R} or one mana of the chosen color.

Clear the Mind

Target player shuffles their graveyard into their library.
Draw a card.

Basilisk Gate

{T}: Add {C}.
{2}, {T}: Target creature gets +X/+X until end of turn, where X is the number of Gates you control. Activate only as a sorcery.

Assault Strobe

Target creature gains double strike until end of turn. (It deals both first-strike and regular combat damage.)

Blight Mamba

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
{1}{G}: Regenerate this creature.

Sea Gate

This land enters tapped.
As this land enters, choose a color other than blue.
{T}: Add {U} or one mana of the chosen color.

Manor Gate

This land enters tapped.
As this land enters, choose a color other than green.
{T}: Add {G} or one mana of the chosen color.

Aspirant's Ascent

Until end of turn, target creature gets +1/+3 and gains flying and toxic 1. (Players dealt combat damage by that creature also get a poison counter.)

Heritage Reclamation

Choose one —
• Destroy target artifact.
• Destroy target enchantment.
• Exile up to one target card from a graveyard. Draw a card.

Heap Gate

{T}: Add {C}.
{1}, {T}: Add one mana of any color.
{1}, {T}, Tap an untapped Gate you control: Create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Tormod's Cryptkeeper

Vigilance
{T}, Sacrifice this creature: Exile target player's graveyard.

Phytoburst

Target creature gets +5/+5 until end of turn.

Black Dragon Gate

This land enters tapped.
As this land enters, choose a color other than black.
{T}: Add {B} or one mana of the chosen color.