msem-instigator

When Titan of Lake Vasil enters, untap up to four target permanents.
{3}{U}: Draw a card.

Nonstoried creatures lose all abilities and have base power and toughness 1/1. (Enchantments and legendary permanents are storied.)

When Titou Louoe, Bayou Shaman enters, create a blue Aura Curse enchantment token named Curse of Impotence attached to target player. The token has enchant player and “Creatures enchanted player controls get -1/-0.”

When To Go Beyond enters, draw a card, then choose a card name.
{2}{U}: Reveal a card you own from outside the game with the chosen name and put it on top of your library.

Creatures you control get +1/+1.
{3}{W}{W}, Sacrifice To a Bright Future: Put a +1/+1 counter on each creature you control.

Winnow (Damage dealt to this creature also causes you to lose that much life.)
Sacrifice Tormented Echo: Target creature gains winnow until end of turn.

Torrent of Ankuliths deals 5 damage to target creature. Create a 1/1 red Elemental creature token.

Trample
{4}{R}{R}: Tortle Tinkerer explores. This ability costs {1} less to activate for each artifact you control. (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.)

Exile up to X target instant and/or sorcery cards with total mana value X or less from your graveyard. You may cast a copy of each card exiled this way without paying its mana cost. Exile Total Recall.

Each player loses 3 life, then discards a card, then sacrifices a creature, an enchantment, a land, a planeswalker and a token. Then exile all graveyards.

Search your library for a card. You may cast it without paying its mana cost if it's a green creature or Revelation spell with mana value X or less. Then shuffle.
Coalesce {X}{X}{G}{G}{G}{G} (You may cast this from your graveyard for {X}{X}{G}{G}{G}{G}. If you do, it enters as a Horror creature after it resolves. Exile it if it would leave the battlefield or not resolve.)

Reach
Assault {5}{G}{G}{G} (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 Towering Hydraffe assaults, create a token that's a copy of it.

Towering Inferno deals X damage to each creature without flying. If a creature you don't control dealt damage this way would die this turn, exile it instead.

Trample
At the beginning of your upkeep, return another creature you control to its owner's hand.

As an additional cost to cast this spell, exile any number of cards from your graveyard. This spell costs {1} less to cast for each card exiled this way.
All creatures get -3/-3 until end of turn.

I, II — Mill two cards. You gain 2 life. (Put the top two cards of your library into your graveyard.)
Discovery — During each of your turns, you may cast a permanent spell from your graveyard.

For each player, you choose from among the permanents that player controls an artifact, a creature, an enchantment, and a planeswalker. Then each player sacrifices all other nonland permanents they control.

Tap target creature, then draw X cards, where X is its mana value.

At the beginning of your upkeep, you may return a nontoken creature you control to its owner's hand. If you do, create a 2/2 green Elk creature token.

All creatures get -2/-2 until end of turn. Remove two loyalty counters from each planeswalker.

{4}{W}{W}: Create a 4/4 white Angel creature token with flying.
{2}{W}{W}: Populate. (Create a token that's a copy of a creature token you control.)

{3}{B}, Discard a card: Each opponent loses 2 life and you gain 2 life.
At the beginning of your upkeep, if there are five or more creature types among cards in your graveyard, you lose 1 life and draw a card.

Experience (Whenever this creature attacks, if it has fewer than three +1/+1 counters on it, put a +1/+1 counter on it.)
{1}{W}, Sacrifice a creature or enchantment: Scry 1, then draw a card. Activate only if Trauma Surgeon has a +1/+1 counter on it.

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Whenever you cast your first instant or sorcery spell each turn, copy that spell. You may choose new targets for the copies.

Destroy target creature. Mill a number of cards equal to its power.