msem-instigator

Marshy Vista enters tapped.
{T}: Add {B} or {R}.
{1}, {T}: Add one mana of any color.

Equipped creature is a Flagbearer in addition to its other types.
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.
Equip {5}

When Shizen, the Thousand Steps enters, draw a card, then choose a creature card name.
Creatures you control with the chosen name get +0/+1 and have hexproof.

Target creature you control fights target creature you don't control, then fights it again.

Whenever a creature you control becomes the target of a spell, that creature gets +3/+3 until end of turn.

Enchant creature you control
Enchanted creature gets +1/+1.
{1}{U}: Return Lightning Draw and enchanted creature to their owners' hands.

Counter target noncreature spell.

Whenever Drownyard Colossus or another creature you control enters, any number of target players each mill cards equal to that creature's toughness.
{2}{U}{B}, {T}: Draw a card, then create a 0/3 blue Crab creature token with “{T}: Target player mills a card.”

When Suraj Militant enters, target creature gets +1/+1 until end of turn.

Flying
Menagerie — When Old-Rune Watcher enters, if there are five or more creature types among creatures you control, draw a card.

Reprise {3}{U} (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.)
Scry 3, then draw a card.

Frenzy 1 (Whenever this creature attacks and isn't blocked, it gets +1/+0 until end of turn.)
Whenever Trading Traitor deals combat damage to a player, you lose life equal to the number of unblocked attacking creatures you control and draw that many cards.

Advance {3}{W} (Cast this for {3}{W} to advance it as it enters. {3}{W}: Advance this as a sorcery.)
Whenever Hrexa Enforcer advances, put a +1/+1 counter on it.

Enchant creature
Whenever enchanted creature attacks or blocks, its controller gets a poison counter.

Spirited (When this enters, you may activate one of its activated abilities without paying its cost.)
{1}, {T}, Discard a card: You gain 4 life.
{2}, {T}, Pay 2 life: Create a 1/1 colorless Construct artifact creature token. It can't block this turn.
{3}, {T}, Sacrifice a permanent: Draw a card.

Slipstream Horizon enters tapped.
{T}: Add {U} or {R}.
{U}{R}, {T}, Sacrifice Slipstream Horizon: Conjure a card named Data-Point into your hand. (It's a sorcery that costs {2} with “Draw a card.”)

Vigilance
As long as it's your turn, other creatures you control get +1/+1.

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

Trample
When Moranai Outriders enters, if it's not a token, create a token that's a copy of it, except it has no mana cost.

At the beginning of combat on your turn, target creature you control with flying gets +1/+1 until end of turn.

As an additional cost to cast this spell, sacrifice a creature.
Target creature gains +4/+4 until end of turn.

Haste
Ruin Shark attacks each turn if able.
Ruin Shark gets +1/+0 and has first strike as long as you've drawn two or more cards this turn.

Double strike
The first spell you cast during each of your turns costs {W}{U}{B}{R}{G} less to cast. This effect reduces only the amount of colored mana you pay.

When Walking Armory enters, return all Equipment cards from your graveyard to the battlefield, then attach them to Walking Armory.