msem-instigator

As an additional cost to cast this spell, put a -1/-1 counter on a creature you control.
Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.

Creatures you control get +0/+1 and can attack as though they didn't have defender.
Whenever three or more creatures you control attack or block, each creature you control assigns combat damage equal to its toughness rather than its power this turn.

{16}, {T}: Time Cube gains “At the beginning of your end step, if it's not an extra turn, take three extra turns after this one” and loses this ability.

This spell costs {2} less to cast and may be cast as though it had flash if an opponent searched their library this turn.
When Ridge Warden enters, exile another target nonland permanent with mana value 4 or less until Ridge Warden leaves the battlefield.

Breach (Whenever this deals combat damage to a player, you may have it become an Aura Curse until your next turn. Attach it to that player.)
Whenever you cast a spell, Daemonspawn deals 1 damage to each cursed opponent.

Enchant creature
When Sylvan Majesty enters, search your library for a Forest card, put it onto the battlefield tapped, then shuffle.
Enchanted creature gets +3/+3.

When Feathered Dancer enters, up to three target creatures can't block this turn.

Flying
Whenever AOSE Skydrone deals combat damage to a player, draw a card.

Create two 1/1 blue Elemental creature tokens with flying.
Reconstruct {7}{U} (You may cast this from your graveyard for its reconstruct cost reduced by the mana value of a permanent you sacrifice as you cast it this way. Then exile this.)

[+1]: Distribute two +1/+1 counters among any number of target creatures you control.
[–1]: Create two 1/1 white Monk creature tokens.
[–6]: Until your next turn, you choose which creatures attack or block and how those creatures attack or block.

{T}, Pay 1 life: Add {W} or {B}.
{2}, {T}, Sacrifice Royal Hospital and another permanent: Draw a card. Activate only during your turn.

When R-12 Lone Digger enters, it deals 3 damage to target player or planeswalker.

Flying
Morph {4}{R}{W} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)
When Ishim of Devilry is turned face up, put a +1/+1 counter on it, then each opponent loses 2 life and you gain 2 life.

When Maaru, Tomb Guardian enters, create three Treasure tokens.
Each Treasure you control is an artifact creature with power and toughness each equal to the number of Treasures you control.

Return target instant or sorcery card from your graveyard to your hand. Forbidden Wisdom deals damage to up to one target creature or planeswalker equal to that card's mana value.
Exile Forbidden Wisdom.

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.)
When Kantra of Avarice enters, target player draws two cards and loses 2 life.

Each player chooses one card in their hand, then discards the rest.

Create three 2/2 red Noble creature tokens with disgraced 1. (Each enters with a -1/-1 counter. Whenever one deals combat damage to a player, remove all -1/-1 counters from it.)

Bulwark — If you control a creature with toughness 4 or greater, each creature you control assigns combat damage equal to its toughness rather than its power this turn.
Creatures you control get +0/+2 until end of turn.

Whenever a creature blocks, Heat of Battle deals 1 damage to that creature's controller.

Enchant creature
Enchanted creature gets +2/+2 as long as it's an Actor. Otherwise, it gets -2/-2.

Nonbasic lands have “Whenever this land becomes tapped, you lose 1 life unless you sacrifice this land.”

Whenever you cast a creature or planeswalker spell, if mana produced by a nonland permanent was spent to cast it, it gains trample and haste until end of turn.
{T}: Add {R} or {G}.

When Wurgelurg dies, each opponent discards three cards, sacrifices three creatures, and loses 3 life. You draw three cards, create three tapped 2/2 black Zombie creature tokens, and gain 3 life.
Foreshadow {7}{B}{B} (You may cast this spell for its foreshadow cost. If you do, also trigger its “dies” abilities when it enters.)

Glitch {1} (Remove one [restriction] for each time you pay the glitch cost.)
Target opponent reveals their hand. You choose a [noncreature,] nonland card [with mana value 3 or less] from among them. That player discards that card.