msem-instigator

When Hatewracked Explorer enters, you may sacrifice an artifact or creature. If you do, crystallize. (Put a +1/+1 counter on a creature you control or create a Treasure.)
{4}{B}{R}, Sacrifice an artifact or creature: Destroy target creature if it was dealt damage this turn.

Head on Collision deals 2 damage to any target.
Leitmotif (If you cast this spell from your hand, exile it as it resolves. When you next cast a spell that shares a color with this card, you may cast this from exile without paying its mana cost.)

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.)

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.

At the beginning of your upkeep, if each opponent controls more lands than you, search your library for a basic land card, reveal it, and put it into your hand, then shuffle.

Flying
If a source without flying would deal damage to you, prevent 2 of that damage.
Crew 5

Whenever Heedless Astronaut attacks, it gets +2/+0 and gains indestructible until end of turn.

When Herald of Darkness enters, destroy up to one target creature with mana value 3 or less.

Whenever Herald of Heroes deals combat damage to a player, reveal the top five cards of your library. You may put a creature card with power 2 or less from among them into your hand. Put the rest on the bottom of your library in any order.

Trample
At the beginning of your end step, if there are two or more +1/+1 counters among creatures you control, return Herald of Might from your graveyard to the battlefield.

When Herald of Teardrops enters, choose one. If you control another Elemental, you may choose both instead.
• Create a 1/1 blue Elemental creature token with flying.
• Put a +1/+1 counter on each of up to two creatures.

Haste
Herald of Unity's power is equal to the number of creatures you control.

Flash
When Herald of Wisdom enters, you may cast target instant or sorcery card with mana value 4 or less from your graveyard without paying its mana cost. If that spell would be put into your graveyard, exile it instead.

Destroy target creature or planeswalker.

Enchant creature
Enchanted creature gets +2/+0.
{2}{B}, Exile Hold Me Down from your graveyard: Return target creature card from your graveyard to your hand.

As Holdsteady Engine enters, choose a card name.
Cards with the chosen name entering the battlefield don't cause abilities to trigger.
Activated abilities of cards with the chosen name can't be activated unless they're mana abilities.

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.)
Hopeless Wanderer can't be blocked.

Trample
Whenever Horrific Progenitor deals damage to a player, for each damage dealt, that player loses 3 life unless they sacrifice a nonland permanent or discard a card.

Return up to one target permanent card and up to one target Horror card from your graveyard to your hand.

Hostile Habitat deals 2 damage to each creature.
Leitmotif (If you cast this spell from your hand, exile it as it resolves. When you next cast a spell that shares a color with this card, you may cast this from exile without paying its mana cost.)

This spell costs {1} less to cast for each creature that attacked this turn.
Hot to the Touch deals X damage to any target.

Hub of Innovation enters tapped.
At the beginning of your upkeep, if you control five or more artifacts, draw a card.
{T}: Add {C}.

Destroy target Human creature.

Target creature you control gets +X/+X until end of turn. It fights target creature you don't control.

{1}{G}{G}, Discard a card: Destroy target artifact or enchantment.
At the beginning of your end step, if twelve or more cards are in your graveyard, create two 3/3 green Beast creature tokens.