msem-instigator

When Unwavering Sentinel enters, for each creature you control, create a white Aura enchantment token named Shield with “Enchant creature” and “If enchanted creature would be destroyed, instead remove all damage from it and sacrifice this Aura” attached to that creature.

Enchant player
When Curse of Nightmares enters, destroy target creature or planeswalker enchanted player controls.
Whenever enchanted player draws a card, they lose 1 life and you gain 1 life.

Once each turn, you may cast a creature spell with mana value less than or equal to the number of names noted for Genetic Breakthrough without paying its mana cost.
{G}, Sacrifice a nontoken creature with a name not noted for Genetic Breakthrough and note its name: Draw cards equal to the sacrificed creature's power, then discard two cards.

{T}: Add {C}.
{T}, Pay 1 life: Add {W} or {B}.

Enchant creature you control
Enchanted creature gets +1/+1 and has ward {1}.
Whenever enchanted creature deals combat damage to a player, choose target creature you control without a permanent named Candlegift attached to it. Create a token that's a copy of Candlegift attached to that creature.
{W}, Sacrifice five enchantments: Create a 5/5 white Angel creature token with flying.

Whenever Portal Inhibitor attacks, exile target nonland card from defending player's graveyard. Copy it. You may cast the copy. (You still pay its costs, including color. Copies of permanents enter as tokens.)

When Silver Gardener enters, create a 1/1 green Saproling creature token.
Unveil {2}{G}{W} ({2}{G}{W}: Transform this. Unveil only as a sorcery.)

Prevent all damage that would be dealt to target attacking or blocking creature this turn.
Inscribed creature gets +1/+1 and has vigilance.
Inscribe {2}{W} ({2}{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.)

Trample
Mentor (Whenever this creature attacks, put a +1/+1 counter on target attacking creature with lesser power.)
Whenever Tribal Guard mentors a creature, that creature gains trample until end of turn.

Flying
{2/B}{2/B}, {T}, Sacrifice Meddling Gargoyle: Target opponent reveals their hand. You choose a nonland card from it. That player discards that card. Activate only as a sorcery.

Choose one —
• Return target creature card from your graveyard to your hand.
• Pay {4}. If you do, return target creature card from your graveyard to the battlefield.

You may put a creature or land card from your hand onto the battlefield. Then each opponent may put a permanent card from their hand onto the battlefield. If one does, you may repeat this process.

At the beginning of each combat, you may have Firefish Conjurer deal 3 damage to target creature you control. If you do, Firefish Conjurer gets +2/+0 and gains flying until end of turn.

(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 Crisis in Nizev enters, exile the top three cards of your library. Until the end of your next turn, you may play those cards.

When Restless Explorer enters, search your library for a land card, reveal it, put it into your hand, then shuffle.

Mark (Whenever this creature attacks, mark target creature until end of turn.)
Whenever a marked creature dies, put a +1/+1 counter on Mei's Collector.

When Blossoming Expanse enters, you may put a basic land card from your hand onto the battlefield tapped.
{1}, {T}: Add one mana of any color.

Trample
Fallen Warden's power and toughness are each equal to the number of creature cards in all graveyards.

Equipped creature gets +1/+1 and has prowess.
Equip {2}

Menace (This creature can't be blocked except by two or more creatures.)
Whenever Slaughtered Steps Taskmaster attacks, you may sacrifice another creature. If you do, Slaughtered Steps Taskmaster gets +2/+0 until end of turn.

Flash
When Intrepid Shooter enters, it deals 2 damage to target attacking creature.

When 1-ST Thankless Companion enters, draw a card.

This spell costs {4} less to cast if a player attacked with four or more creatures this turn.
End the turn.

Create a 1/1 green Saproling creature token for each nonland permanent card in your graveyard.

Destroy target creature. Mill two cards.