msem-instigator

Vigilance

Reveal cards from the top of your library until three creature and/or land cards are revealed this way. Put all creature and/or land cards revealed this way into your hand and the rest into your graveyard.

Counter target spell unless its controller pays {2}.
Lifecycle {3} ({3}, Discard this card: Create two tapped 1/1 colorless Elemental creature tokens.)

Defender
When Wall of Ivy enters the battlefield, create a Vial token. (It's an artifact with “{1}, Sacrifice this and another permanent: Draw a card. Activate only during your turn.”)

Defender
When Wall of Rime enters the battlefield, tap target creature an opponent controls. That creature doesn't untap during its controller's next untap step.

Defender
Whenever Wall of Seclusion blocks a creature, that creature doesn't untap during its controller's next untap step.

{T}, Pay 1 life: Add {B} or {G}.
{2}, {T}, Sacrifice Walled Garden and another permanent: Draw a card. Activate only during your turn.

Angels, Demons, Faeries, and Spirits you control get +1/+1.
{2}{W}{B}, Pay 1 life, Discard a card: Create a tapped 1/1 white Spirit creature token with flying.

Lifelink, haste
Wanton Cleaver has first strike as long as it's attacking.

Each instant and sorcery card in your graveyard gains agonize until end of turn.
Agonize (You may cast this card from your graveyard by putting a -1/-1 counter on a creature you control in addition to paying its other costs. Then exile this card.)

First strike
Wither (This deals damage to creatures in the form of -1/-1 counters.)

Vigilance, reach
Watchful Authority can block an additional creature each combat.

Whenever Wavering Sorcerer attacks, you may switch its power and toughness until end of turn.
Unveil {3}{U}{R} ({3}{U}{R}: Transform this. Unveil only as a sorcery.)

Counter up to one target spell unless its controller pays {2}. Until end of turn, you may cast spells as though they had flash.

{T}, Pay 1 life: Add {U} or {B}.
{2}, {T}, Sacrifice Weathered Wharf and another permanent: Draw a card. Activate only during your turn.

At the beginning of your upkeep, discard a card and create a Vial token. (It's an artifact with “{1}, Sacrifice this and another permanent: Draw a card. Activate only during your turn.”)

Wharf Lumper can't be blocked by creatures with greater power.
Whenever Wharf Lumper attacks, mill a card. If that card was an instant or sorcery, Wharf Lumper gets +3/+0 until end of turn.

Deathtouch
{T}: Add one mana of any color.

Flash
When Witch of the Veil enters, if it was cast, you may sacrifice a creature. If you do, return that card to the battlefield under its owner's control.

When Witch's Invitation enters the battlefield, you may put a -1/-1 counter on target creature.
{2}, {T}: Tap target creature with a -1/-1 counter on it.

Harmony — Germinate. (Put a +1/+1 counter on a creature or create a 1/1 green Saproling creature token.)
When Woopip Chef enters the battlefield, harmonize. (Trigger up to one harmony of one permanent you control.)

Flash
When Wormwood's Agent dies, create a Vial token. (It's an artifact with “{1}, Sacrifice this and another permanent: Draw a card. Activate only during your turn.”)

[+2]: Put a -1/-1 counter on or remove a -1/-1 counter from up to one target creature.
[–1]: Draw a card, then each player sacrifices a nonland permanent.
[–10]: Destroy all nonland permanents you don't control.

Haste
When Wretched Merfolk enters the battlefield, target creature can't block this turn.

Whenever you cast an instant or sorcery spell, put a loyalty counter on Xenocrata and tap up to one target permanent.
[0]: Each opponent can't untap more than three permanents during their next untap step.
[–3]: Xenocrata deals 6 damage divided as you choose among any number of target creatures and/or planeswalkers.
[–9]: Cast any number of instant and/or sorcery cards you own in exile and from your graveyard without paying their mana costs.