msem-instigator

Whenever you make first contact, create a Treasure token. (You make first contact the first time each turn you cast a spell with a name not in your graveyard or control already.)
{T}, Return an artifact with mana value X you control to its owner's hand: You may cast a spell with mana value X plus 1 or less and with a different name from your hand without paying its mana cost.

Whenever an artifact you control enters, look at the top card of your library. If that card's mana value is less than or equal to that artifact's mana value, you may reveal it and put that card into your hand. Otherwise, put it on the top or bottom of your library.

Indestructible
Whenever Hannaru the Conqueror attacks, put a +1/+1 counter on each creature you control.

Enchant creature
When Hannaru's Courage enters, create a 1/1 white Soldier creature token with vigilance.
Enchanted creature gets +1/+1 and has vigilance.

When Hannaru's Spear enters, create Hannaru's Aegis, a legendary white Equipment artifact token with “Equipped creature gets +1/+2 and has vigilance” and equip {2}.
Equipped creature gets +2/+1 and has first strike.
Equip {2}

Flying, trample
Whenever Hao'Tai, the Ancient One deals combat damage to a player, exile the top four cards of that player's library. Until end of turn, you may cast instant, sorcery, and creature cards from among those exiled cards, and you may spend mana as though it were mana of any color to cast them.

Flying
Whenever Hao'Tai deals combat damage to a player, that player exiles the top five cards of their library and separates them into two piles. Put an ember counter on each card in the pile of your choice. You may play cards from exile with ember counters for as long as they remain exiled.

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.

Vanishing 3 (This creature enters with three time counters on it. At the beginning of your upkeep, remove a time counter from it. When the last is removed, sacrifice it.)
When Hapless Chronomancer dies, if it had no time counters on it, return target instant or sorcery card from your graveyard to your hand.

Creatures you control get +2/+0 until end of turn. Creatures target player controls gain winnow until end of turn. (Damage dealt to it also causes its controller to lose that much life.)

Frenzy 1 (Whenever this creature attacks and isn't blocked, it gets +1/+0 until end of turn.)
Whenever Haploc Blooddrinker becomes blocked, it gains lifelink until end of turn.

Frenzy 1 (Whenever this creature attacks and isn't blocked, it gets +1/+0 until end of turn.)
Whenever Haploc Striker attacks and isn't blocked, you may cast target instant or sorcery card from your graveyard if its mana value is less than or equal to Haploc Striker's power. Exile that card instead of putting it into your graveyard as it resolves.

When Happily Retired enters, exile target creature you don't control with mana value 3 or less until Happily Retired leaves the battlefield.
{1}, Sacrifice Happily Retired: Return target exiled creature card you own that's on an Adventure to your hand. Activate only as a sorcery.

Slipstream (This creature can't be blocked as long as only creatures with slipstream are attacking.)
Whenever Happy Manta deals combat damage to a player, draw a card for each card type among spells you've cast this turn.

Planeswalker spells you cast cost {1} less to cast for each storied permanent you control. (Enchantments and legendary permanents are storied.)

Flying, trample
Harbinger of Falling Skies enters with X +1/+1 counters on it.
Whenever Harbinger of Falling Skies attacks, you may remove a +1/+1 counter from it. If you do, draw a card.

Flying
At the beginning of your first main phase, you may put any number of land cards from your hand onto the battlefield, then draw a card for each land put onto the battlefield this way.

{U}, Give yourself a lore counter: Scry 1. This ability costs {2} more to activate for each lore counter you have.
{6}{U}, Remove three lore counters from yourself, Sacrifice Harbinger of Giradrus: Draw seven cards, then create two 4/4 red Dragon creature tokens with flying.

When Harbinger of Growth enters, create a 1/1 green Saproling creature token.
{1}{G}, Sacrifice Harbinger of Growth: Populate. (Create a token that's a copy of a creature token you control.)

If a player would gain life, that player adds that much {C} instead.

Flying
Assault {2}{B} (Whenever this attacks, if it has no +1/+1 counters on it, you may pay its assault cost to put a +1/+1 counter on it.)
When Harbinger of Locusts assaults, you may search your library for an Insect card, reveal it, put it into your hand, then shuffle.

Hard Bargain deals 2 damage to target creature or planeswalker an opponent controls and you gain 2 life. Then if you have more life than that opponent, draw a card.

Whenever one or more Rogues you control attack, you may pay 1 life. If you do, draw a card.

Civilized — Hard-Working Oxen gets +3/+0 as long as you control an artifact, a creature, and an enchantment.

When Hardened Explorer enters, choose one —
• Destroy target artifact.
• Put a +1/+1 counter on Hardened Explorer. It gains haste.