msem-instigator

When Arms Merchant enters, look at the top four cards of your library. You may reveal an artifact card from among them and put it into your hand. Put the rest on the bottom of your library in any order.

This spell costs {1} less to cast for each +1/+1 counter among creatures you control.
Hoof Cliff Heartminer enters with four +1/+1 counters on it.
Whenever Hoof Cliff Heartminer or another creature you control leaves the battlefield, you may put its +1/+1 counters on another target creature you control.

Enchant opponent
When Pathless Shallows enters, exile target creature enchanted player controls until Pathless Shallows leaves the battlefield.
Enchanted player can't cast spells with the same name as the exiled card.

Destroy target creature with mana value X or less.

You may play an additional land this turn. Scry 1.

Vigilance
When Traveling Duo enters, create a 1/1 colorless Servo artifact creature token.

Frigid Highlands enters tapped unless you control an Island.
{T}: Add {R} or {G}.

As Living Sandstorm enters, choose predator or prey.
Whenever Living Sandstorm attacks,
• Predator — It gets +1/+1 until end of turn.
• Prey — Scry 2.

Flash
If a spell or ability would cause an opponent to create a token, instead you create that token and that player creates a 1/1 blue Fish creature token.

Players can cast spells only during their own turns.
Each player can't cast more than one spell each turn.

Target permanent and all other permanents with the same name as that permanent gain indestructible until end of turn.

This spell has flash as long as you control another enchantment.
When Kernel Quarantine enters, exile all other creatures until Kernel Quarantine leaves the battlefield.

{G}: Each player exiles a card from their graveyard. If an instant or sorcery card is exiled this way, put a +1/+1 counter on Earthfeeder Worm.
Remove X +1/+1 counters from Earthfeeder Worm and sacrifice it: Exile X target cards from graveyards.

Target creature gets +2/+1 and gains haste until end of turn.
Agonize (You may cast this card from your graveyard by putting a -1/-1 counter on a creature you control in addition to paying its other costs. Then exile this card.)

Dafiqi Falconer gets +X/+X, where X is the amount of life you've gained this turn.
As long as your life total is greater than your starting life total, Dafiqi Falconer has flying.

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.)
Deathtouch

Reach
Whenever Thicketwalker attacks, you may tap or untap target land.

{U}: Sea Strider gets +1/-1 until end of turn.
{U}: Sea Strider gets -1/+1 until end of turn.

Scavenging Soldier has first strike as long as it's attacking.
Attain {3}{W} ({3}{W}: Transform this. Spend at least three colors of mana to activate this, and only as a sorcery.)

At the beginning of combat on each opponent's turn, if you control three or more enchantments, choose target creature. Prevent all combat damage that creature would deal this turn.
{2}{W}: You gain 2 life and scry 1.

When Trench Breaker enters, put target creature on top of its owner's library.

Encourage ({T}: Another target creature you control gets +1/+1 until end of turn. Encourage only as a sorcery.)
Whenever Paladin's Attendant encourages a creature, that creature gains first strike until end of turn.

Harmony — Search your library for a basic land or Desert card, reveal it, and put it into your hand. Then shuffle.
When Trumpeting Pathmaker enters, harmonize. (Trigger up to one harmony of a permanent you control.)

Return up to two target creature cards with mana value X or less from your graveyard to the battlefield. They can't block this turn.

This spell costs {2} less to cast if you control a legendary creature.
Search your library for a creature or land card, reveal it, put it into your hand, then shuffle.