msem-instigator

Destroy target creature or planeswalker.

Whenever Hero's Henchman attacks, another target creature you control gets +1/+1 until end of turn.

Search your library for a basic land card and put it onto the battlefield, then shuffle. Create an Idol token. (It's an artifact with “{1}, Sacrifice this artifact: Put a +1/+1 counter on target creature. Activate only as a sorcery.”)

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

Flying
Whenever Heroes of Wars Past attacks, attacking Human creatures get +1/+1 and gain flying until end of turn.

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.

When Heroic Aspiration enters, you may search your library for a creature card with an Adventure, reveal it, put it into your hand, then shuffle.
At the beginning of your end step, if you cast both a creature spell and a noncreature spell this turn, Heroic Aspiration deals 2 damage to each opponent and you gain 2 life.

Lifelink
Tap three other untapped creatures and/or artifacts you control: Transform Heroic Crusader.

Return target creature card with mana value 3 or less from your graveyard to the battlefield.
Draw a card.

First strike, lifelink
Once each turn, when another nontoken creature you control dies, you may create a 2/2 white Elk Spirit creature token with first strike and lifelink named Fawn of Hesediel.

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.)

[+1]: Add {G}{U}{R}. Spend this mana only to cast creature spells.
[–2]: Reveal the top card of your library. If it's a creature card that costs less than the last spell you cast this turn, you may put it onto the battlefield. Otherwise, draw a card.
[–7]: Target creature becomes a legendary 20/20 green creature named Illusion of Kaur with hexproof and trample until end of turn.

Prowess
Whenever Hethwyr Warcaster or another Wizard you control enters, you may draw a card.

When Hex Maniac enters, return target non-Human creature card from your graveyard to your hand.

Flash
When Hexfang Ascetic enters, return target spell to its owner's hand.

When Hextwister Hare enters, if you control another Shaman or there's a Shaman card in your graveyard, each opponent discards a card.

Flash
Whenever another permanent dies, put a +1/+1 counter on Heyu.
{1}{G}: Heyu becomes a colorless Island land until end of turn.

At the beginning of your upkeep, put a +1/+1 counter on Heyu, Immortal Hunter.
Whenever Heyu becomes the target of a spell or ability an opponent controls, counter it if Heyu has the greatest power among creatures on the battlefield.

{1}{G}, Discard Hibiscus Snapdragon: Create a Treasure token.
Scavenge {4}{G} ({4}{G}, Exile this card from your graveyard: Put a number of +1/+1 counters equal to this card's power on target creature. Scavenge only as a sorcery.)

Flash
When Hidden Sprout enters, put a +1/+1 counter on target creature.

Whenever a player casts a spell, that player reveals cards from the top of their library until they reveal two land cards, then puts all cards revealed this way into their graveyard.

When Hideaway Agent enters, gain control of target nonland permanent with mana value 3 or less for as long as you control Hideaway Agent.

Target creature gains flying and gets +1/+0 for each card in your hand until end of turn.
Fuse (You may cast one or both halves of this card from your hand.)

Whenever a player casts a noncreature spell, create a 1/1 white Human Soldier creature token.
{1}{U}, Tap four untapped creatures you control: Counter target noncreature spell.

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Whenever you cast a noncreature spell, you gain life equal to its mana value.