msem-instigator

Target creature gets +X/+X and gains vigilance until your next turn, where X is the number of creatures you control.

Discard a card: Search your library for a card with the same mana value as the discarded card, reveal it, put it into your hand, then shuffle. Activate only as a sorcery and only once each turn.

If you would draw a card while your library has no cards in it, you win the game instead.

At the beginning of each opponent's upkeep, if that player owns a card in exile, they lose 1 life and you gain 1 life.
At the beginning of your upkeep, if you own a card in exile, you gain 1 life and each opponent loses 1 life.

Vigilance
Whenever you make first contact, put a +1/+1 counter on Volarian Sightseer. (You make first contact the first time each turn you cast a spell with a name not in your graveyard or control already.)

Haste
{2}{U}: Volatile Alchemist gains vigilance until end of turn and can't be blocked this turn.

Volcanic Catastrophe deals 3 damage to any target. If a permanent dealt damage this way would die this turn, instead exile it and its controller's graveyard.

At the beginning of your first main phase, exile the top card of your library. Until end of turn, you may play that card.
Invocation — Whenever you spend four or more mana to cast a spell or activate an ability during your turn, create a 3/1 red Elemental Spirit creature token with trample and haste.

Volcanic Rain deals damage to target creature or planeswalker equal to the number of lands you control.

When Voldaren Crypt-Guard enters, create a Weapon token. (It's an Equipment artifact with “Equipped creature gets +1/+1” and equip {2}.)

Whenever you innovate, put a loyalty counter on Volta the Innovator. (You innovate as you cast a spell, draw a card, or have a land enter beyond the first of each in a turn.)
[–2]: If you would draw a card this turn beyond the first, draw twice that many cards instead.
[–3]: Whenever you cast your second spell this turn, copy it. You may choose new targets for the copy.

Eureka! (At the beginning of each end step, you get a research counter if you cast a spell this turn. Then if you have eight or more research counters, remove them and create a Masterpiece token of your choice.)
[+1]: Untap up to one target artifact you control.
[–2]: Draw three cards. Then discard two cards unless you discard an artifact card.

{1}{B}, Sacrifice another creature: Put a +1/+1 counter on Voracious Ghoul.

Equipped creature gets +2/+2.
Whenever equipped creature attacks, exile target nonland permanent defending player controls. For as long as that card remains exiled, its owner may cast it. (They still pay its costs.)
Equip {2}

[+1]: Search your library for a basic land card, reveal it, put it into your hand, then shuffle.
[–3]: You get an emblem with “{1}{G}: You may play an additional land this turn.”
[–6]: Creatures you control gain trample and have base power and toughness X/X until end of turn, where X is the number of lands you control.

Adorned — As long as Voyaging Devout is equipped and/or enchanted, creatures with power less than its power can't block it.

Ward {2} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)
Whenever you cast a spell during an opponent's turn, tap target nonland permanent.

Overcast — Whenever you cast a spell, create a 1/1 black Bird creature token with flying and menace if {C} was spent to cast it.
Whenever three or more creatures you control deal combat damage to a player, return target card from your graveyard to your hand.

{T}: Add {B}.
{B}, {T}: Target creature gains menace until end of turn.

Whenever another non-Zombie creature you control dies, create a tapped 2/2 black Zombie creature token.
{B}, Sacrifice a creature: Target creature gains deathtouch until end of turn.

Look at the top four cards of your library. Put one of those cards into your hand and the rest into your graveyard.
Flashback {2}{B}{G} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Whenever Wadepool Frog attacks, it gains flying until end of turn.

Flying
Wailing Soul has hexproof as long as it's not attacking or blocking.

At the beginning of your upkeep, each player discards a card.
Whenever Waking Watcher attacks, if defending player has no cards in hand, it gets +3/+3 and gains menace until end of turn.

Play with the top card of your library revealed.
Spells you cast that share a creature type with the top card of your library cost {1} less to cast.