msem-instigator

Augmented — If you've spent {W}{U}{B}{R}{G} to cast spells this turn, you may cast this spell without paying its mana cost.
Counter target spell.

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.

Add {W}{U}{B}{R}{G}. Spend this mana only to cast spells from your graveyard or activate abilities of cards in your graveyard.

Discard your hand, shuffle your library, then draw three cards. You may cast a nonland card from your hand without paying its mana cost.
Acquiesce (If you cast this spell from your hand, exile it as it resolves. When one or more creatures you control deal combat damage to an opponent, you may cast this card from exile without paying its mana cost.)

Flying, trample
When Whisper in the Rift enters, target player mills half their library, rounded down.
When Whisper in the Rift dies, you may cast up to two instant, sorcery, and/or creature cards from among opponent's graveyards without paying their mana cost.

Escalate {B} (Pay this cost for each mode chosen beyond the first.)
Choose one or more —
• Wicked Blow deals 3 damage to target player or planeswalker.
• Wicked Blow deals 3 damage to target creature.
• You gain 3 life.

Wild Realms enters tapped unless you control two or more other lands.
{T}: Add {G}.
{T}, Pay 1 life: Add {R} or {W}.

When Wild Waypoint enters, create a 1/1 green Scout creature token.
{T}: Add {B}, {G}, or {U}.

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

Prowess
Curse spells you cast cost {W}{U}{B}{R}{G} less to cast. This effect reduces only the amount of colored mana you pay.
Whenever you cast a Curse spell, you may draw a card.

Whenever Witchfinder Artur enters or attacks, each opponent mills two cards and loses 2 life.
Whenever you cast an instant or sorcery spell, you may exile target instant or sorcery card with mana value less than that spell's mana value from an opponent's graveyard. If you do, cast a copy of the exiled card without paying its mana cost.

Whenever Withering Husk enters or attacks, you may discard a card and pay 1 life. If you do, draw a card, then each opponent loses 1 life.
Recite {R} (You may cast this creature from your graveyard for its recite cost. If you do, exile it when it enters or if it would leave the battlefield.)

Double strike
The first spell you cast during each of your turns costs {W}{U}{B}{R}{G} less to cast. This effect reduces only the amount of colored mana you pay.

({T}: Add {B}.)
Wretched Sanctuary enters tapped with two sanctum counters on it.
{T}, Remove a sanctum counter from Wretched Sanctuary: Add {U} or {R}.

When Wu, the Shackled enters, you may have an opponent gain control of it. If you do, draw two cards.
At the beginning of your upkeep, if you don't own Wu, it fights another target creature you control and its owner draws a card.

Vigilance, trample
Pay 3 life: You choose if and how target creature attacks or blocks this turn. You choose before its controller declares other attackers or blockers. Activate only once each turn.

Flying
{2}: Copy target activated or triggered ability you control. You may choose new targets for the copy.
{W}{U}{B}{R}{G}: Search your library for a card, exile it, then shuffle. Until the end of your next turn, you may play that card.

{1}, {T}, Sacrifice two or more nonland permanents: Return target creature card from your graveyard to the battlefield. If permanents with total mana value 4 or greater were sacrificed this way, draw a card.

[+1]: Put a +1/+1 counter on up to one target creature, then put your choice of a menace, deathtouch, or trample counter on it.
[0]: Target creature or Xiong planeswalker you control fights target creature you don't control.
[–1]: Target player sacrifices a permanent.

[0]: Sacrifice a creature. When you do, Xiong Mao, Survivalist deals damage to any target equal to that creature's power, then put a number of loyalty counters on Xiong Mao equal to that creature's toughness.
[–2]: Return up to two target creature cards from your graveyard to your hand.
[–6]: You get an emblem with “Whenever a creature you control dies, you may draw cards equal to its power, then you may gain life equal to its toughness.”

[+1]: Create a 1/1 red Panda Monk creature token with “{T}: Target player exiles a card from their graveyard.”
[0]: You may sacrifice a creature. If you do, search your library for a creature card and a land card, reveal them, put them into your hand, then shuffle.
[–2]: Xiong Mao deals damage to target creature or planeswalker equal to the greatest power among creatures you control and cards in your graveyard.
[–7]: Any number of players' life totals each become equal to the number of cards in their graveyard.

[+2]: Create a 3/3 red Panda creature token.
[–X]: Sacrifice a creature. If you do, search your library for a creature card with mana value less than or equal to X plus the sacrificed creature's mana value. Put that card onto the battlefield, then shuffle.
[–6]: You get an emblem with “Whenever a creature dies, this emblem deals damage equal to that creature's power to any target and you draw that many cards.”

[+1]: You may sacrifice a creature. If you do, return a creature card with lesser mana value from your graveyard to the battlefield.
[–1]: Other creatures and planeswalkers you control gain indestructible and can't have counters removed from them until your next turn.
[–X]: Exile X target cards from graveyards. Xiong Mao deals X damage to any target.

Archive 5 (As this enters, shuffle the top five cards of your main library into a new face up library. Sacrifice this after the archived library is empty.)
Recursive — Xirix's Study has all nonrecursive abilities of all Study cards in graveyards except for their archive abilities.

You may activate loyalty abilities of Xirix, the Usurper during extra turns any time you could cast an instant.
[+1]: Look at the top three cards of your library. Put one of them into your hand and the rest into your graveyard.
[–2]: Destroy each nonland, non-Xirix permanent with the greatest mana value among non-Xirix permanents on the battlefield.
[–6]: Put target permanent card from a graveyard onto the battlefield under your control.