msem-instigator

Masked Impersonator can't be blocked.
Art of war — At the beginning of your end step, if Masked Impersonator dealt damage to an opponent this turn, you may have it become a copy of target creature you control except it has this ability.

Prowess
Whenever you cast a noncreature spell, noncreature spells you cast cost {1} less to cast until end of turn.

Art of war — At the beginning of your end step, if Kowareta Scrounger dealt damage to an opponent this turn, you may search your library for an artifact card, reveal it, put it into your hand, then shuffle.

This spell costs {1} less to cast for each spell you cast this turn.
When Jidai Serpent enters, draw two cards.

Draw a card.
Inscribe {1}{U} ({1}{U}: Exile this card from your hand inscribed on a creature you control. Whenever that creature attacks, its controller may cast a copy of the inscribed card without paying its mana cost. Inscribe only as a sorcery.)

Enchant land you don't control
Whenever enchanted land becomes tapped, you may draw a card.

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
When Hinasa Mystic enters, draw a card.

Untap target creature you control. It gains hexproof until end of turn.

Return target nonland permanent and all other permanents with the same name as that permanent to their owners' hands.
Draw a card.

At the beginning of each player's draw step, that player draws an additional card.

Create two 1/1 colorless Samurai creature token. Those creatures gain first strike until end of turn.

Prevent all damage that would be dealt to target attacking or blocking creature this turn.
Inscribed creature gets +1/+1 and has vigilance.
Inscribe {2}{W} ({2}{W}: Exile this card from your hand inscribed on a creature you control. Whenever that creature attacks, its controller may cast a copy of the inscribed card without paying its mana cost. Inscribe only as a sorcery.)

Creatures you control get +1/+1 until end of turn.
Inscribe {2}{W} ({2}{W}: Exile this card from your hand inscribed on a creature you control. Whenever that creature attacks, its controller may cast a copy of the inscribed card without paying its mana cost. Inscribe only as a sorcery.)

Vigilance
Art of war — At the beginning of your end step, if Teikoku Samurai dealt damage to an opponent this turn, put a +1/+1 counter on it.

Art of war — At the beginning of your end step, if Teikoku Daimyo dealt damage to an opponent this turn, put a +1/+1 counter on each creature you control that attacked this turn.

First strike
Art of war — At the beginning of your end step, if Teikoku Cavalry dealt damage to an opponent this turn, put a +1/+1 counter on it.

When Taiyohata's Dominion enters, draw a card, then choose a creature card name.
Once each turn, when a creature with the chosen name you control enters, you may create a 1/1 colorless Samurai creature token.

Art of war — At the beginning of your end step, if Sheraku Elite dealt damage to an opponent this turn, put a +1/+1 counter on it.

Flying
Sakura Spirit has lifelink as long as it's equipped, enchanted, or has a card inscribed onto it.

Protector of the Gates can't attack unless it's equipped, enchanted, or has a card inscribed onto it.

Exile target nontoken permanent you control, then return that card to the battlefield under its owner's control.

Equipped creature gets +2/+2.
Art of war — At the beginning of your end step, if equipped creature dealt damage to an opponent this turn, create a 1/1 colorless Samurai creature token.
Equip {2}

Double strike
Art of war — At the beginning of your end step, if Kogane's Swordmaster dealt damage to an opponent this turn, put a +1/+1 counter on it.

At the beginning of each upkeep you may pay {W}. If you do, tap target creature.

Tap any number of untapped creatures you control. You gain 4 life for each creature tapped this way.