msem-instigator

Gain control of target creature if its power is less than or equal to the number of cards in your hand.
Quickdraw {4}{U}{U} (When a creature you control blocks or becomes blocked, you may cast this spell for {4}{U}{U}.)

Archive 3 (As this enters, shuffle the top three cards of your main library into a new face up library. Sacrifice this after the archived library is empty.)
You may cast the top card of the archived library. Whenever you do, copy that spell. You may choose new targets for the copy.

[+1]: Add {R} or {G}. You can't spend this mana to cast an Elf spell.
[–2]: Winona, the Heretic deals 4 damage to any target. If that target is an Elf, Winona deals 4 damage to that Elf's controller.
[–6]: Until end of turn, any time you could cast an instant, you may pay {R}. When you do, Winona deals 2 damage to any target.

Vigilance, reach
When Winter Widow enters, you may destroy target creature with flying.

Deathtouch
Whenever another creature named Winter's Whelp you control enters, you draw a card and you lose 1 life.

Armed — Winterborn Savage gets +1/+1 and has vigilance as long as it's equipped.

Enchantments you control have hexproof.
Wira Inti, Skyfather can't attack or block unless you control five or more enchantments.
At the beginning of combat on your turn, up to two other target enchantments you control each become a creature in addition to their other types and have flying, vigilance, and base power and toughness 4/4.

Flash
When Wiretapper enters, choose one —
• Exile target spell. For as long as that card remains exiled, its owner may play it. A spell cast this way costs {2} more to cast.
• Create a copy of the card with target spell's name. You may cast the copy. (You still pay its costs.)

Look at the top three cards of your library. Exile one, put one into your hand, and put the rest on the bottom of your library. Wisdom Beyond Age deals damage to target creature or planeswalker equal to the exiled card's mana value.

Target player shuffles any number of target cards from their graveyard into their library.
Draw a card.

Exile the top four cards of your library. You may cast instant and/or sorcery cards exiled this way until the end of your next turn.

Converge — Draw a card for each color of mana spent to cast Wisdom of the Leylines. Then discard a card.

Whenever a creature is returned to your hand, scry 1.
{4}{G}{U}: Reveal the top card of your library. If it's a permanent card, you may put it onto the battlefield.

When Wise Farseer Chini enters, create a tapped colorless land token named Far-Off Lands with “{T}: Add one mana of any color.”

Wise Old Oak enters tapped unless you control a basic Forest.
{T}: Add {G}.
{3}{G}{G}: Until end of turn, Wise Old Oak becomes a 4/4 green Treefolk creature with “Whenever this creature deals combat damage to a player, draw a card.” It's still a land.

Cast a copy of target creature or Revelation card in your graveyard without paying its mana cost. If a Revelation is cast this way, it enters as a Horror creature after it resolves.
Exile Wish to See.

Harness (You may tap a creature you control as you cast this spell. If you do, reduce this spell's mana cost by that creature's power.)
You gain X life.

Flying

{T}: Add {R}. Put a charge counter on Wistful Automaton.
Remove three charge counters from Wistful Automaton: Transform it.

When Wistful Fox enters, reveal the top eight cards of your library. You may put a creature card from among them into your hand. Put the rest on the bottom of your library in a random order.

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

Enspirit (As you cast this spell, you may exile a nonenchantment creature you control until this leaves the battlefield or fails to resolve. Reduce this spell's cost by the exiled card's mana value.)
You may have Witch of Shifting Waters enter as a copy of any creature on the battlefield, except it's an enchantment in addition to its other types.

Flying
When Witch of Spring's Promise enters, shuffle any number of cards from your hand into your library, then draw that many cards plus one.

Deathtouch
At the beginning of your end step, create a 1/1 black Rat creature token with “This creature can't block.”
{1}{B}, {T}, Sacrifice three other creatures: Each opponent discards a card and loses 2 life. You draw a card and gain 2 life.

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.