msem-instigator

Creatures with defender you control can attack as though they didn't have defender.
Each creature you control assigns combat damage equal to its toughness rather than its power.

When Harvest Blighter enters, create a black Aura Curse enchantment token named Rotting Away attached to target player. The token has enchant player and “Whenever a creature enters under enchanted player's control, if it has toughness 2 or greater, put a -1/-1 counter on that creature.”

Cast this spell only during your turn and only during the declare attackers step or with its acquiesce ability.
Untap all creatures you control. After this phase, there is an additional combat phase.
Acquiesce (If you cast this spell from your hand, exile it as it resolves. When one or more creatures you control deal combat damage to an opponent, you may cast this card from exile without paying its mana cost.)

Enchant land
Whenever enchanted land is tapped for mana, its controller adds one mana of any color.

When a creature scavenges Harvest Reaper, search your library for a colorless card, reveal it, put it into your hand, then shuffle.
Scavenge {2} ({2}, 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.)

At the beginning of your upkeep, Harvest the Stars deals 4 damage to any target.

Whenever Harvester of Secrets or another creature enters from your graveyard, you may draw a card.
Unearth {2}{U}{B} ({2}{U}{B}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the end step or if it would leave the battlefield. Unearth only as a sorcery.)

Harvest (You may tap any number of creatures you control as you cast this spell. If you do, reduce this spell's mana cost by their total power.)
Create a 5/5 colorless Scarecrow artifact creature token with “This creature can't block or harvest.”
Flashback {8}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Whenever you cast an instant or sorcery spell from your hand, put that card onto the battlefield face down as a 2/2 creature instead of putting it into your graveyard as it resolves.
Whenever a face-down creature you control deals combat damage to an opponent, you may exile it. If you do, you may cast it without paying its mana cost.

Whenever another creature you control enters, you may gain 1 life.
Whenever a creature enters under an opponent's control, you may have that player lose 1 life.

Menace
Art of war — At the beginning of your end step, if Hashiro's Infiltrator dealt damage to an opponent this turn, that player discards a card.

When Hashiro's Vanguard enters, each player sacrifices a nontoken creature.

Discard your hand. Creatures you control get +X/+0 and gain first strike until end of turn, where X is the number of cards discarded this way.

Prevent all damage that would be dealt to target player this turn.
Fabled {1}{W}{W}{W} (Then if you cast this for its fabled cost, put it onto the battlefield transformed attached to that player.)

You may activate loyalty abilities of target planeswalker you control an additional time this turn.
Fabled {1}{U}{U} (Then if you cast this for its fabled cost, put it onto the battlefield transformed attached to that planeswalker.)

When Hate-Driven Arsonist enters, you may have it deal X damage to target creature or planeswalker, where X is the number of instant and sorcery cards in your graveyard.

Target player discards two cards and loses 2 life. Scry 2. (To scry 2, look at the top two cards of your library, then put any number of them on the bottom of your library and the rest on top in any order.)

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.

Each player discards their hand, then draws cards equal to the greatest number of cards discarded this way.

Reprise {3}{R} (As you cast an instant or sorcery spell, you may exile one card with reprise from your graveyard and pay its reprise cost. If you do, add its effects to that spell.)
Hatsuo's Maneuver deals 1 damage to any target. Create a number of 1/1 red Warrior creature tokens equal to the damage dealt by this spell.

First strike
{1}{R}: Hatsuo, Honored General and other Warrior creatures you control get +1/+0 until end of turn.

Haughty Chateau enters tapped unless you have two or more opponents.
{T}: Add {W} or {B}.

When Haughty Paladin enters, you may sacrifice another artifact or creature. If you do, tap all creatures your opponents control.

Whenever you cast a spell during an opponent's turn, Haughty Priest deals 1 damage to that player.

Defender
Civilized — As long as you control an artifact, a creature, and an enchantment, Hauling Hippopotamus can attack as though it didn't have defender.