msem-instigator

Flying
Cadence (Whenever you cast a spell, if its mana value is greater than this creature's power, put a +1/+1 counter on this creature.)

When Healing Center enters, you gain 2 life.
{T}: Add {C}.

When Healing Potion enters, scry 1, then draw a card.
{2}, {T}, Sacrifice Healing Potion: You gain 4 life.

Heart of Carü Mapu enters tapped.
{T}: Add X mana in any combination of colors, where X is the number of basic land types among lands you control.

At the beginning of your upkeep, create a 1/1 green Saproling creature token.
Whenever a creature you control dies, put a +1/+1 counter on Heart of Spores.
{X}{G}: Move X +1/+1 counters from Heart of Spores onto target creature. Activate only as a sorcery.

{T}: Add {C}.
Wanderlust — {T}: Add one mana of any color. Activate only if you control four or more differently named lands. If you control seven or more, you may add three mana of that color instead.

Menace
When Heart of the Deadwood enters, destroy up to one target creature, then put up to one target creature card from a graveyard onto the battlefield under your control.

({T}: Add {G} or {W}.)
Heart of the Glade enters tapped unless you control a basic Forest or a basic Plains.

Menace
Spirited (When this creature enters, you may activate one of its activated abilities without paying its cost.)
{3}{R}: Another target creature you control gains menace until end of turn.

Trample
Whenever you cast a noncreature spell, crystallize. If you create a Treasure this way, Heartforge Savant deals 1 damage to you for each Treasure you've created this turn. (Put a +1/+1 counter on a creature you control or create a Treasure.)

Wither (This deals damage to creatures in the form of -1/-1 counters.)
{X}{R}: Hearth Dweller gets +X/+0 until end of turn.

Menace
If another Dwarf or Elf you control would deal damage to an opponent or permanent an opponent controls, it deals that much damage plus 1 instead.
{2}{R}: Create a 1/1 red Dwarf creature token.

Flying, vigilance, deathtouch, lifelink

If one or more counters would be put on a creature you control, that many plus one of each of those kinds of counters are put on that permanent instead.

Flying
When Heartless Host enters, arm target creature. (Create a colorless Equipment artifact token with “Equipped creature gets +1/+0” and equip {2}, then attach it to that creature.)

At the beginning of your upkeep, if you have less life than an opponent, you lose 1 life and you draw a card.

Menace
Sacrifice a Goblin: Heartless Warleader gets +2/+2 until end of turn.

Deathtouch
Whenever another creature dies, its controller discards a card at random.

Augmented — Whenever you cast a spell from your hand, if you've spent {W}{U}{B}{R}{G} to cast spells this turn, exile cards from the top of your library until you reveal a nonland card with mana value less than that spell's mana value. You may cast that card without paying its mana cost. Put the revealed cards not cast this way on the bottom of your library in a random order.

Kicker {2}{B} (You may pay an additional {2}{B} as you cast this spell.)
Flying
When Heartstabber Mosquito enters, if it was kicked, destroy target creature.

Enchant creature
When Heartstrings leaves the battlefield, exile enchanted creature.
Whenever enchanted creature attacks or blocks, exile it at end of combat.

Creature spells you cast cost {1} less to cast.

Whenever you attack, you may pay {R}{W}. If you do, create a tapped and attacking token that's a copy of target attacking creature. Sacrifice the token at the beginning of the next end step.

Reach

Whenever you scry, you gain 1 life for each card you looked at while scrying this way.