msem-instigator

{T}: Add {C}.
{T}: Add one mana of any color. Activate only if two or more land cards are in your graveyard.

Flash
Reach
Glimmerbark Treant enters with X +1/+1 counters on it.
When Glimmerbark Treant leaves the battlefield, you gain life equal to its power.

Destroy target creature or planeswalker. You gain 1 life and that permanent's controller loses 1 life.

Trample, prowess

[+1]: You gain 1 life. Put a +1/+1 counter on up to one target creature.
[–3]: Exile target creature. Its controller gains life equal to its power.
[–8]: You get an emblem with “Creatures you control get +1/+1 and have double strike and lifelink.”

Enchant creature
When Kalku Initiation enters, you lose 3 life and discard a card.
Enchanted creature gets +3/+2, has ward {2}, and has “Whenever this creature deals damage to a player, draw two cards.”

Treacherous Oasis enters tapped.
{T}: Add {U} or {B}.
{2}{U}{B}: Until end of turn, Treacherous Oasis becomes a Crocodile creature in addition to its other types. It can't be blocked this turn.
Scavenge {1}{U}{B}

[+1]: You gain 1 life for each creature card in your graveyard.
[–4]: Exile another target nonland permanent.
[–X]: Return target permanent card with mana value X or less from your graveyard to the battlefield.

As Den of Vice enters, you may pay 3 life. If you don't, it enters tapped.
{T}: Add {U}, {B}, or {R}.

Meteor Volley deals 3 damage to each creature.
Reprise {4}{R}{R} (As you cast an instant or sorcery spell, you may exile one card with reprise from your graveyard and pay its reprise cost. If you do, add its effects to that spell.)

Modular Mercenary gets +1/+0 and has first strike as long as you control a creature with a +1/+1 counter on it.

Flying

Landfall — Whenever a land you control enters, Duskwood Vanguard gets +1/+1 until end of turn.

[+2]: Create a 2/2 red Werewolf creature token with first strike and haste.
[–3]: Tanya deals 3 damage to each creature that's not a Wolf or a Werewolf.
[–8]: For each permanent your opponents control, that player sacrifices it unless they have Tanya deal 2 damage to them.

Counter target creature spell.
Draw a card.

Target opponent exiles cards from the top of their library until X land cards are exiled, where X is the number of land cards in your graveyard.

Vigilance, haste
At the beginning of each player's upkeep, if that player has the lowest life total or is tied for the lowest life total, they gain control of Protector of the Innocent.

Skulking Claw can't be blocked by creatures with greater power.
Skulking Claw gets +1/+0 for each unblocked attacking creature you control.

As long as you control an Island, you may cast this spell as a copy of any creature on the battlefield. (This includes casting cost.)

At the beginning of your upkeep, you may put a +1/+1 counter on target creature.

Slipstream (This creature can't be blocked as long as only creatures with slipstream are attacking.)
Crew 1 (Tap any number of creatures you control with total power 1 or greater: This Vehicle becomes an artifact creature until end of turn.)

Target creature you control deals damage equal to its power to target creature you don't control.
Whenever a creature you control with deathtouch deals damage to an opponent, you may sacrifice that creature. If you do, return Shedding of the Coils from your graveyard to your hand.

Flying, lifelink, haste
At the beginning of the end step, sacrifice Helix Entity.

Slay Them in the Aisles deals 2 damage to each non-Actor creature.

Menace
At the beginning of your end step, if you gained or lost life this turn, look at the top card of your library. You may reveal it and put it into your hand. If you do, you lose life equal to its mana value. If you don't, you may put it into your graveyard.