msem-instigator

{T}, Sacrifice Worldshaper Adept: Choose two basic land types. Create a tapped colorless land token of the chosen types.

Whenever equipped creature deals combat damage to a player, destroy all permanents other than Worldslayer.
Equip {5}

Vigilance
Whenever a creature you control survives damage, it explores. (Reveal the top card of your library. Put it into your hand if it's a land. Otherwise, put a +1/+1 counter on this creature, then you may put that card in your graveyard.)

Whenever one or more creatures you control attack, you may put a progress counter on Worldwide Reach.
[progress 2+] Whenever you cast a noncreature spell, creatures you control get +1/+1 until end of turn.
[progress 4+] Whenever you cast a noncreature spell, creatures you control gain lifelink until end of turn.
Whenever you cast a noncreature spell, creatures you control gain lifelink until end of turn.

{2}{W}, Exile Worldwise Ascetic from your graveyard: Create a green Aura enchantment token named Years of Experience attached to target creature. The token has enchant creature and “Enchanted creature gets +2/+2.” Activate only as a sorcery.

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.”)

Vigilance
When Worn Peacekeeper dies, create a 1/1 white Soldier creature token with vigilance.

Whenever equipped creature attacks, it gets +2/+2 and gains trample until end of turn.
Equip {2}

{T}: Scry 1.
{1}{U}, {T}: Draw a card.

Each opponent sacrifices an artifact.
Scry 1.
Coalesce {6}{R} (You may cast this from your graveyard for {6}{R}. If you do, it enters as a Horror creature after it resolves. Exile it if it would leave the battlefield or not resolve.)

Vanishing 4 (This permanent enters with four time counters on it. At the beginning of your upkeep, remove a time counter from it. When the last is removed, sacrifice it.)
Whenever a time counter is removed from Worship in Vain, discard your hand, then draw a card for each time counter on Worship in Vain.

When Worship of the Sun enters, draw a card, then choose a card name.
At the beginning of your upkeep, you may tap three untapped creatures you control. If you do, search your library for an enchantment card with the chosen name, put it onto the battlefield, then shuffle.

Ferocious — At the beginning of each combat, if you control a creature with power 4 or greater, Worshipper Whelp gets +2/+0 until end of turn.

Destroy target land. Then, judge target creature you control. (Honor it by putting a +1/+1 counter on it or condemn it by sacrificing it to draw a card.)

Target creature you control gets +3/+3 and gains lifelink and trample until end of turn.
Inscribe {3}{G}{W} ({3}{G}{W}: Exile this card from your hand inscribed on a creature you control. Whenever that creature attacks, its controller may cast a copy of the inscribed card without paying its mana cost. Inscribe only as a sorcery.)

{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast Aura or Aurashaper spells.

Wraith of the Fens gets +2/+2 as long as you've gained life this turn.

Choose target creature you control. If it has a +1/+1 counter on it, put an additional +1/+1 counter on it. Then it fights target creature you don't control.

Enchant creature you control
Enchanted creature gets +1/+1 and has hexproof and “{T}: Target player mills two cards.”
Whenever you play a land, untap enchanted creature.

Colossal 2—{4}{B}{B} (You may cast this for its colossal cost to have it enter with two +1/+1 counters; or pay {4}{B}{B} as a sorcery: Put two +1/+1 counters on it if it has none.)
Menace
When Wretched Catoblepas's colossal ability puts one or more counters on it, each opponent sacrifices a creature.

Flying
Assault {2}{B} (Whenever this attacks, if it has no +1/+1 counters on it, you may pay its assault cost to put a +1/+1 counter on it.)
When Wretched Lammasu assaults, each opponent discards a card.

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

({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}.

Whenever a nontoken creature you control enters, if it wasn't cast, put a +1/+1 counter on Wretched Skulker.
{3}{W}, Sacrifice Wretched Skulker: Exile target nonland permanent with mana value less than Wretched Skulker's power.

When Wretched Spawn enters, you may return target permanent to its owner's hand. If you do, that player discards a card.
Unearth {4}{U}{B} ({4}{U}{B}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the end step or if it would leave the battlefield. Unearth only as a sorcery.)