msem-instigator

If one or more counters would be put on a permanent you control, you may have that many counters plus one or that many counters minus one put on that permanent instead.

Trample
As an additional cost to cast creature spells, you may sacrifice a permanent. If you do, that spell costs {2} less to cast and that creature enters with an additional +1/+1 counter on it.

Trample
Other Dwarves and Elves you control get +1/+1.
If Harl and Finn or another Dwarf or Elf you control entering the battlefield or attacking causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

{1}, {T}, Move a -1/-1 counter from another creature onto Harried Apothecary: Each opponent loses 1 life and you gain that much life.

Whenever Haunted Prodigy attacks, you may tap target creature.
Unveil {2}{W}{U} ({2}{W}{U}: Transform this. Unveil only as a sorcery.)

Ward—Sacrifice a permanent.
Whenever a player sacrifices a permanent, put a +1/+1 counter on Hayat, Hungering Bakhtak.
Surpass {4}{B}{G} ({4}{B}{G}: Transform this creature. This costs {1} less to activate for each counter on it. Activate only as a sorcery.)

When Heedless Lovers enters, you may return target Citizen card from your graveyard to your hand.
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.)

[+2]: Until end of turn, up to one target creature you control gets +3/+3 and gains trample and vigilance.
[–2]: Destroy target artifact, enchantment, or tapped creature.
[–3]: Create a 1/1 green Insect creature token, a 2/2 white Cat creature token, and a 3/3 red Ox creature token.
[–8]: Until end of turn, creatures you control get +X/+X and gain trample and vigilance, where X is the number of creatures you control.

Whenever you draw a card, put a +1/+1 counter on Highborn Meditant.

When Historiamancer enters, return target instant or sorcery card from your graveyard to your hand.

Trample
Hollow Survivor's power and toughness are each equal to the number of cards in your hand.
Whenever Hollow Survivor deals combat damage to a player, draw a card.

Hollowghast, the Iron Phantom enters with three +1/+1 counters on it.
If damage would be dealt to Hollowghast, prevent that damage. Remove a +1/+1 counter from Hollowghast.

At the beginning of your upkeep, put a crop counter on Homestead.
{G/W}, Remove a crop counter from Homestead: Put a +1/+1 counter on target creature.
{G/W}, Remove three crop counters from Homestead: Put a +1/+1 counter on each creature you control.

When Hooded Inquirers enters, draw two cards.

You may cast Hunter of the Moon-Serpent from your graveyard as long as you gained life this turn.

Haste
Whenever a nonbasic land becomes untapped, its controller loses 1 life.

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)

Haste
When Inciter of Spirits Scorned enters, return target creature card with mana value 3 or less from your graveyard to the battlefield. It gains haste. Sacrifice it at the beginning of the next end step.

Haste
When Inciting Bard enters, other creatures you control get +1/+0 and gain haste until end of turn.

Each opponent plays with the top card of their library revealed.
During each of your turns, you may play one card from the top of an opponents' library, and you may spend mana as though it were mana of any color to cast that spell.

Whenever Inkwell Daggers enters or attacks, proliferate. (Choose any number of permanents and/or players with counters on them, then give each another counter of each kind already there.)

Mill three cards, then you may return a creature or land card from your graveyard to your hand.

When Inspired Blade enters, if you control another Warrior, draw a card.

Untap all creatures you control.
Draw a card.

{T}: Izahl, the Stormbringer deals 1 damage to any target.
Whenever you cast a noncreature spell, you may untap target creature you control.