msem-instigator

This spell costs {3} less to cast if a creature died this turn.
Hatefire deals 6 damage to target creature or planeswalker. If that creature or planeswalker would die this turn, exile it instead.

Vigilance
At the beginning of your end step, if you control two or more Spirits and/or creatures with flying, transform Haunted Waif.

Flying
Whenever Havengul Banshee attacks, each creature defending player controls gets -1/-0 until end of turn.
{3}{U}: Return Havengul Banshee from your graveyard to the battlefield transformed under your control attached to target opponent. Activate only as a sorcery.

Hazy Summits enters tapped.
{T}: Add {R} or {W}.
{1}, {T}: Add one mana of any color.

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.

Flying
Whenever Hecatomb Haunter enters or attacks, up to one other target nonland permanent phases out. (Treat it and anything attached to it as though they don't exist until its controller's next turn.)

Lifelink
Embellish {2}{B} (If you cast this spell for {2}{B}, create a 1/1 blue Thopter artifact creature token with flying when it enters.)

Colossal 5—{8}{W}{W} (You may cast this for its colossal cost to have it enter with five +1/+1 counters; or pay {8}{W}{W} as a sorcery: Put five +1/+1 counters on it if it has none.)
Ward {5}
When Hekaton Dismantler's colossal ability puts one or more counters on it, tap each creature you don't control. Those creatures don't untap during their controller's next 100 untap steps.

Enchant creature you control
When Heliod's Benefaction enters, scry 2.
Enchanted creature gets +1/+1 and has lifelink.

Whenever you scry, you gain life equal to the number of cards looked at while scrying this way.

Indestructible
As long as your devotion to white is less than five, Heliod isn't a creature.
If an effect would create one or more kinds of tokens under your control, it creates an additional token of each kind.
{3}{W}: Put a +1/+1 counter on each other creature you control. Activate only as a sorcery.

This spell costs {X} less to cast, where X is your devotion to green. (Each {G} in the mana costs of permanents you control counts toward your devotion to green.)
Trample

Hellfire Crater enters tapped. When it enters, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)
{T}: Add {B} or {R}.

Menace, trample
Hellfreaks gets +1/+0 for each Curse you control.
Hellfreaks gets +1/+0 for each instant and sorcery card you own in exile and in your graveyard.

When Hellion Devastator enters, destroy up to one target nonland permanent with mana value 3 or less.
Cycling {2} ({2}, Discard this card: Draw a card.)

Flying
Whenever Hellkite Omnivore attacks, you may have it consume. If you do, put a +1/+1 counter on Hellkite Omnivore. When a creature is sacrificed this way, Hellkite Omnivore deals 3 damage to any target. (To consume, sacrifice another creature or exile a creature card from your graveyard.)

Hellkite's Decree deals 3 damage divided as you choose among one, two, or three target creatures and/or planeswalkers.
Cycling {2} ({2}, Discard this card: Draw a card.)

Haste
The first instant or sorcery spell you cast each turn costs {1} less to cast.
{R}, {T}, Sacrifice Hellspark Prankster: Change the target of target spell with a single target.

When Helvault, Shard of the Moon enters, for each player, exile up to one other target nonland permanent that player controls until Helvault, Shard of the Moon leaves the battlefield. When you exile a permanent you control this way, draw three cards.
{T}: Add {C}{C}{C}{C}{C}.
Cycling {2} ({2}, Discard this card: Draw a card.)

Encourage ({T}: Another target creature you control gets +1/+1 until end of turn. Encourage only as a sorcery.)
Whenever a creature deals combat damage to a player, if it was encouraged by Herald of the White Orchid this turn, create a 1/1 white Soldier creature token.

{T}: Add one mana of any color.
{7}, {T}, Sacrifice Hero's Statue: Draw three cards.

Colossal 2—{6}{W}{W} (You may cast this for its colossal cost to have it enter with two +1/+1 counters; or pay {6}{W}{W} as a sorcery: Put two +1/+1 counters on it if it has none.)
When Heroes' Adversary's colossal ability puts one or more counters on it, exile target creature an opponent controls until Heroes' Adversary leaves the battlefield.

Reach
As long as you control an artifact or an enchantment, Heron's Grace Patrol gets +1/+1 and has vigilance.
{2}{G}{W}, {T}: Mill three cards. You may return a permanent card milled this way to your hand.

Whenever you cast an instant or sorcery spell, each opponent loses 1 life and you gain 1 life.

Encourage ({T}: Another target creature you control gets +1/+1 until end of turn. Encourage only as a sorcery.)
{T}: Add {G}.
Whenever Hierarch Ranger encourages a creature, add one mana of any color.