msem-instigator

Distorted (This creature can be blocked by tapped creatures but not untapped creatures.)

As an additional cost to cast this spell, sacrifice a land and discard a card.
Draw three cards.

{B}, {T}, Discard a card: Create a 1/1 black Skeleton creature token.
{B}, {T}, Sacrifice a creature: Put a +1/+1 counter on each Skeleton you control.

When Shawlbinder enters, if you control a Desert, exile another target permanent. Return that card to the battlefield under its owner's control at the beginning of the next end step.

Mentor (Whenever this creature attacks, put a +1/+1 counter on target attacking creature with lesser power.)
{2}, Sacrifice a creature: Put a +1/+1 counter on Desert Marauder.

When Dutiful Counselor enters, adjudicate. (Create a white Aura enchantment token with enchant creature and “Sacrifice this token: Untap enchanted creature” attached to target creature.)
Whenever an Aura you control enters, you may pay {1}. If you do, target creature gets +1/+1 until end of turn.

(Transform this if it's not attached to a creature. Pay {3}{G} as a sorcery to unattach it.)
Enchant creature you control
Elven Mount's rider gets +3/+3 and has trample.

Trample
Whenever a creature you don't control dies, you gain 2 life.
Whenever you gain life, put that many +1/+1 counters on target creature you control.

{T}: Add {C}.
{1}, {T}: Add one mana of any color. This ability costs {1} less to activate if there are three or more colors among cards in your graveyard.

Enchant creature
Enchanted creature's activated abilities can't be activated.
Prevent all damage that would be dealt by enchanted creature.

If an opponent would gain life, that player loses that much life instead.

Scry 2 if a player lost life this turn. You draw two cards and you lose 2 life.

Whenever equipped creature deals combat damage to a player, put a +1/+1 counter on it, then proliferate. (You choose any number of permanents and/or players with counters on them, then give each another kind of a counter already there.)
Equip {2}

At the beginning of each upkeep, if it's an extra turn, end the turn.
If a player would search a library, that player searches the top four cards of that library instead.

Flying
Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
Lifelink (Damage dealt by this creature also causes you to gain that much life.)

Players can't cast spells with mana value greater than the number of dissent counters on Kazimir's Ban.
{2}: Put a dissent counter on Kazimir's Ban. Any player may activate this ability.

When Saia's Protege enters, gain control of target artifact or enchantment for as long as you control Saia's Protege.

Whenever you cast a spell that's white, blue, black, or green, put a +1/+1 counter on Hesitant Vanguard.
Surpass {5}{R} ({5}{R}: Transform this creature. This costs {1} less to activate for each counter on it. Activate only as a sorcery.)

Harmony — You may pay {1}{G}. If you do, create a 3/3 green Beast creature token.
When Wildheart Chorister enters, harmonize. (Trigger up to one harmony of a permanent you control.)

{T}: Add {G}.

{1}, {T}, Sacrifice a creature: Draw a card and put a corpse counter on Carnage Throne. Then if there are three or more corpse counters on it, remove those counters, transform it, then untap it. Activate only as a sorcery.

Target opponent reveals their hand, exiles each nonland card from it, then conjures a card named Data-Point into their hand for each card exiled this way. (It's a sorcery that costs {2} with “Draw a card.”)

Lifelink
Triggered abilities of creatures you control that would trigger only when that creature enters instead trigger whenever you gain life for the first time each turn.

Deathtouch
When Vision Beyond the Waters enters, each player sacrifices two creatures other than this creature.

Armed — Whenever Beragnian Intimidator attacks, if it's equipped, target creature can't block this turn.