msem-instigator

Until end of turn, target player can't cast noncreature spells, and that player can't activate abilities that aren't mana abilities.
Draw a card.

{T}: Add {R} or {W}. You lose 1 life unless you have less life than an opponent.

This spell can't be countered.
{R/G}: Target spell can't be countered.

Activated abilities of nonland permanents cost {2} more to activate.

({T}: Add {U} or {R}.)
Whenever Crystal Cavern becomes tapped, you lose 1 life unless you control two or more basic lands.

Vigilance
Players can't untap more than two lands during their untap steps.

Obscoriate deals 4 damage to target creature or planeswalker. The next time that permanent would die this turn, instead put a basalt counter on it, it becomes a Mountain land named Charred Remains, loses all other card types, and gains “At the beginning of your upkeep, Charred Remains deals 1 damage to you.” (It has “{T}: Add {R}” and loses abilities it already had.)

Enchant land (Target a land as you cast this. This card enters attached to that land.)
Enchanted land has “{T}: Add one mana of any color” and “At the beginning of each upkeep, untap this land.”

Deathtouch

When Burglar Cat enters, exile the top card of target opponent's library. You may play that card during any turn you attacked with a Rogue, and you may spend mana as though it were mana of any color to cast it.

Menace
When Minotaur Skullsmasher enters, choose a nonland card type. Then target opponent reveals their hand. You choose a card of the chosen type from it. That player discards that card.

Flying
Concord — At the beginning of your upkeep, if there are four or more card types among permanents you control, exile the top card of your library. You may cast that card this turn without paying its mana cost.

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
When Kalime Charger enters, you may have another target creature you control gain trample until end of turn.

Whenever another creature named Crinster Sheepdog enters, nourish 1. (To nourish 1, either put a +1/+1 counter on this creature or create a 1/1 white Citizen creature token.)

When Cloven Forms enters, reveal the top three cards of your library. Put all creature cards revealed this way into your hand and the rest into your graveyard.
{5}{G}{G}{G}, Exile Cloven Forms: Put a creature card from or hand or command zone onto the battlefield. Create a token that's a copy of it, except the token isn't legendary.

Harvest (You may tap any number of creatures you control as you cast this spell. If you do, reduce this spell's mana cost by their total power.)
Destroy target creature.

Target creature gets -2/-2 until end of turn.
{3}{B}{B}, Exile Ominous Wind from your graveyard: Each creature gets -2/-2 until end of turn. Activate only as a sorcery.

Target player discards two cards.

When Goblin Sniper dies, you may pay {R}. If you do, it deals 2 damage to target opponent or planeswalker.

Flying
As Tal, Locus Sentry enters, choose a noncreature, nonland card type.
Spells of the chosen type cost {1} more to cast.

[+1]: Each opponent loses 1 life for each card you've drawn this turn. Then you draw a card.
[–2]: Shi Hou, the Sun King deals 2 damage to target creature or planeswalker and you gain 2 life. If that permanent was already dealt damage this turn, destroy it.

Until end of turn, target creature gets +1/+1 and gains lifelink.

Persist (When this creature dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

Destroy target tapped creature. You gain 2 life.

Pressure {3}{B}{B} (You may cast this spell for its pressure cost if seven or more cards are in your graveyard.)
Each player sacrifices a creature. Put a creature card from a graveyard onto the battlefield under your control.