msem-instigator

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

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.

Flash
If a spell or ability an opponent controls would cause you to discard a creature card, you may put that card onto the battlefield instead.

Flash
When Highpoint Guru enters, scry X, where X is the number of Monks you control.

Flying, lifelink

Assault {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 Hilaback Outriders assaults, it gains menace until end of turn.

When Hired Kalak enters, put target card from your graveyard on top of your library.

Whenever a creature dies, exile it.
Hiroto Jaakuna has all activated abilities of creature cards exiled with Hiroto Jaakuna.

When Hisana-no-Oni enters, gain control of target creature until Hisana-no-Oni leaves the battlefield.

When Historiamancer enters, return target instant or sorcery card from your graveyard to your hand.

Choose three. You may choose the same mode more than once.
• You draw a card and you lose 1 life.
• Target opponent discards a card and loses 1 life.

Pressure {1}{U} (You may cast this spell for its pressure cost if seven or more cards are in your graveyard.)
Exile up to two target nonland permanents you control, then return them to the battlefield under their owner's control.

Reach
When Hoarding Arachnid dies, draw a card.

When Hollow Hooligan enters, up to two target creatures can't block this turn.
Mirage {1}{R} (You may cast this spell as though it had flash for its mirage cost. If you do, sacrifice it at the beginning of the next cleanup step.)

Flying, deathtouch
Revive {3}{B} ({3}{B}, Exile this card from your graveyard: Create a token that's a copy of this card, except it has no mana cost. Activate this ability only any time you could cast a sorcery.)

When Holy War enters, create three 1/1 white Cleric creature tokens.
Creature tokens you control have first strike and lifelink.

While an opponent is choosing targets as part of casting a spell they control or activating an ability they control, that player must choose at least one Flagbearer on the battlefield if able.
Persist (When this creature dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

Flying
Mentor (Whenever this creature attacks, put a +1/+1 counter on target attacking creature with lesser power.)
Whenever Honorable Mentor mentors a creature, that creature and Honorable Mentor each gain first strike until end of turn.

When Hoof Cliff Caretaker enters, return target card of an opponent's choice from your graveyard to your hand.

Menace
Whenever Hope Wrangler attacks, target attacking creature with lesser power gains menace until end of turn.

Lifelink
Whenever you gain life, you may transform Hopeful Caretaker. If you don't, put a +1/+1 counter on it.

Armed — Whenever Hordedriver Enthusiast attacks, if it's equipped, creatures you control get +1/+0 and gain trample until end of turn.

Chosen one ({W}{U}{B}{R}{G}: Transform this permanent.)
Whenever you cast an instant or sorcery spell, scry 1, then Horizon Augur gets +1/+1 until end of turn.

Trample

Flying, vigilance
At the beginning of your end step, if a creature you control dealt combat damage to an opponent this turn, put a +1/+1 counter on Horizon Prophet.