msem-instigator

Search your library for a basic land card and put it onto the battlefield tapped, then shuffle. You gain 1 life for each land you control.

CySec Nexus enters tapped.
{T}: Add {W} or {U}.
{W}{U}, {T}: Create a Function token with “Flash.” Activate only as a sorcery. (It's an enchantment. As you cast an instant or sorcery spell, sacrifice any number of Functions to add their effects to that spell.)

Embellish {4}{W} (If you cast this spell for {4}{W}, create a 1/1 blue Thopter artifact creature token with flying when it enters.)
Equipped creature gets +2/+2.
Whenever an artifact creature you control enters, you may attach Etherium Staff to it.
Equip {2}

(As an Encounter enters, choose an opponent to protect it. You and others can attack it. When defense counters are removed, create a 0/0 Army token if you don't control one, then put that many +1/+1 counters on a Army you control.)
When Nizev Rising enters, return target instant or sorcery card from your graveyard to your hand.

When Neo-Alchemist enters, you may reappropriate. If you do, distribute two +1/+1 counters among creatures you control. Otherwise, put a +1/+1 counter on up to one target creature you control. (To reappropriate, exile exactly two cards from your hand and/or graveyard.)

({T}: Add {B}.)
Corpsebed enters tapped.
When Corpsebed enters, exile up to two target cards from graveyards.

Choose one —
• Prevent all damage that would be dealt by creatures this turn.
• Harmonize twice. (Trigger up to one harmony of a permanent you control.)

Whenever you cast your second spell each turn, Expressive Performer deals 1 damage to each opponent.
{3}{R}, {T}, Exert Expressive Performer: It deals 2 damage to each player. (An exerted creature won't untap during your next untap step.)

Return target creature card from your graveyard to your hand. You may trigger a death knell of that card.

When Verdant Curtain Naturalist enters, you gain 3 life.
{T}: Add one mana of any color.

Trample
Whenever a creature dies, put a +1/+1 counter on Venomclaw Skitterer. You gain 1 life.

Prowess
Gusma's Emissary gets +1/+1 as long as you control a black or green permanent.

Creature tokens you control get +1/+1.
Whenever Thyra, Winter's Warden enters or attacks, you may pay {1}{G/W}. If you do, create Bruga, a legendary 2/2 green and white Wolf creature token.

Whenever Skysworn Savior attacks, you may return another creature you control to its owner's hand. If you do, Skysworn Savior gets +2/+2 and gains flying until end of turn.

Target creature you control deals damage equal to its power to target creature you don't control.

[+1]: Scry 2. Whenever one or more creatures you control deal combat damage to a player this turn, draw a card.
[–2]: Create a token that's a copy of target creature you control, except the token is 4/4 and has vigilance.
[–7]: You get an emblem with “At the beginning of your draw step, draw two additional cards” and “Creatures you control get +1/+1 for each card you've drawn this turn.”

Counter target creature spell, planeswalker spell, or activated ability.

This spell costs {1} less to cast for each instant and sorcery card in your graveyard.
Fiery Explosion deals 5 damage to target creature or planeswalker.

Prevent all combat damage that would be dealt to and dealt by creatures this turn.

Creatures with power greater than Dashing Rogue's power can't block it.

You may cast target card in an opponent's graveyard without paying its mana cost.
Flashback {4}{B}{G}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Memorial Ground enters tapped.
{T}: Add {C}.
{4}, {T}, Sacrifice Memorial Ground: Return target card from your graveyard to your hand.

Return up to two target creatures and/or artifacts to their owners' hands. For each permanent returned to its owner's hand this way, forebode. (Create a tapped colorless Omen artifact token with “{T}, Discard a card, Sacrifice this artifact: Draw a card.”)

Enchant creature
Enchanted creature gets +2/+0.
{2}{B}, Exile Hold Me Down from your graveyard: Return target creature card from your graveyard to your hand.

Reach, vigilance
When Amorphous Tyrant enters, another target creature you control deals damage equal to its power to target creature or planeswalker you don't control.
Evoke {G} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters.)