msem-instigator

Reach, trample
{1}{G}: You may remove a counter from a creature you control. If you do, tap that creature and it gains indestructible until end of turn.

{7}{G}: Distribute three +1/+1 counters among up to three target creatures you control. This ability costs {2} less to activate if you control a legendary creature.

Flash
Flying
Whenever H13 Wasp enters or you cast an another spell with flash or an instant, exile up to one target nonland permanent. Return that card to the battlefield under its owner's control at the beginning of the next end step.

{2}, Sacrifice a creature or artifact: Hadak's Guardian deals 2 damage to any target.

Attacking creatures you control get +1/+0.

Whenever one or more creature cards leave your graveyard, Hadik's Cohort deals 2 damage to target opponent.

Whenever Hadik's Striker is dealt damage, you gain that much life.

Flying
Whenever Haerthach, the Wight King deals combat damage to a player, you may sacrifice another creature. When you do, create a 1/1 white Spirit creature token with flying. Return the sacrificed card to the battlefield tapped and under your control at the beginning of the next end step.

Tribute 1 (As this creature enters, an opponent of your choice may put a +1/+1 counter on it.)
When Haggard Jackal enters, if tribute wasn't paid, each opponent discards a card.

Foresight — Whenever you draw your second card each turn, Haggler's Hound gets +1/+1 and can't be blocked by creatures with power 2 or less until end of turn.

Equipped creature gets +3/+2.
Equip {4}
Hail of Blades's equip ability costs {4} less to activate if it targets an equipped creature.

Haste
{2}{W}, {T}: Hair-Trigger Marshall deals 2 damage to target blocking creature.

Survivors you control get +1/+1.

Survivors you control have vigilance.

Heroic — Whenever you cast a spell that targets Halcyon Hoplite, Halcyon Hoplite gains flying until end of turn.
When Halcyon Hoplite dies, if it was enchanted, create a 1/1 white Bird creature token with flying.

Puzzlebox (Begin the game with this and another card you own from outside the game in the command zone, locked. That card is face down until you unlock this.)
{1}, Sacrifice two Clues: Unlock Hall of Lost Histories and put the revealed card into your hand.

When Hall of Remembrance enters, create two 1/1 white Spirit creature tokens with flying.
Whenever a Spirit you control enters, you gain 1 life.

Enchant player
Creature tokens enchanted player controls get +1/+1.

Vigilance
The first instant or sorcery spell you cast each turn has conspire. (As you cast that spell, you may tap two untapped creatures you control that share a color with it. When you do, copy it and you may choose a new target for the copy.)

Flying
When Hallowed Executioner enters, it deals 2 damage to each creature without flying.

{T}: Add {C}. You gain 1 life.

Flying
When Hallowed Perspective enters, investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)
You may exert Hallowed Perspective as it attacks. When you do, until your next turn, you may cast spells as though they had flash. (An exerted creature won't untap during your next untap step.)

Enchant land
Enchanted land has “{T}: Tap target creature.”

Flash
Enchant creature
Enchanted creature gets -3/-0 and doesn't untap during its controller's untap step.

When Halskrow Street Scavenger enters, if a creature died under your control this turn, create a 2/2 green Wolf creature token.