msem-instigator

Flash (You may cast this spell any time you could cast an instant.)
Defender
When Weary Steward enters, prevent all combat damage target creature would deal this turn.

If a source would deal damage to a creature this turn, prevent all but 1 of that damage.

Whenever you attack or block with one or more other creatures, Wehre-District Patrollers gets +1/+0 and gains first strike until end of turn.

Enchant creature
Enchanted creature gets +2/+2 as long as it's legendary. Otherwise, it can't attack or block.
When enchanted creature dies, if it's legendary, return that card to its owner's hand.

Enchant creature
Enchanted creature has flying.
{2}: Tap enchanted creature.

Whenever West Ward Purifier becomes tapped, you gain 1 life.

You gain 5 life and draw a card. Then if you've cast spells named When the Stars Align five times this game, you win the game.
Augmented — If you've spent {W}{U}{B}{R}{G} to cast spells this turn, you may shuffle When the Stars Align into your library.

Flash
Whenever Whimsical Dancer enters or is exerted, target creature gets +1/+0 and gains first strike until end of turn.
You may exert Whimsical Dancer as it attacks. (An exerted creature won't untap during your next untap step.)

Flying, lifelink
Creatures entering or leaving the battlefield don't cause abilities to trigger unless that creature is in a pack. (Two or more creatures a player controls with equal power are in a pack.)

Enchant creature
Enchanted creature can't attack or block.
{2}{U}: Return Whiplash and enchanted creature to their owners' hands.

Create a 1/1 white Spirit creature token with flying.
Whenever a nontoken creature you control dies, you may pay {W} and exile Whispered Wishes from your graveyard. If you do, create a 1/1 white Spirit creature token with flying.

Double strike

Vigilance

Alpha (You may have this creature enter with a +1/+1 counter on it. If you do, it becomes alpha and can only attack alone.)

When Whiterun Ordainer enters, you gain 4 life.

Flying (This creature can't be blocked except by creatures with flying or reach.)
Lifelink (Damage dealt by this creature also causes you to gain that much life.)

When Wilderness Forager enters, you may reappropriate. If you do, gain 6 life. Otherwise, gain 3 life. (To reappropriate, exile exactly two cards from your hand and/or graveyard.)

Create two 1/1 colorless Samurai creature token. Those creatures gain first strike until end of turn.

Create a 1/1 green and white Mouse Soldier creature token with vigilance and a 1/1 white and black Badger Cleric creature token with lifelink.

Flying
Whenever Wind Savant attacks, harmonize. (Trigger up to one harmony of a permanent you control.)
Harmony — Wind Savant gets +1/+1 until end of turn.

Flying
Windwatch Eagle has vigilance as long as it has a +1/+1 counter on it.

Flying
Windwise Courier has indestructible as long as you've revealed a card from your hand this turn.

Flying
Experience (Whenever this creature attacks, if it has fewer than three +1/+1 counters on it, put a +1/+1 counter on it.)
As long as Wings of Trust has three or more +1/+1 counters on it, it has lifelink and vigilance.

Flying
Revive {1}{B}{B} ({1}{B}{B}, Exile this card from your graveyard: Create a token that's a copy of it except it has no mana cost. Revive only as a sorcery.)