msem-instigator

When War of Resources enters, recruit. (Create a 0/0 white Soldier Army creature token, then put a +1/+1 counter on each Army you control.)
Whenever a creature you control dies, each opponent loses 1 life.

{1}{W}: Artifact creatures you control get +1/+1 until end of turn. Activate only once each turn.

Flash
When Aokara Redeemer enters, exile another target permanent you control. Return that card to the battlefield under your control at the beginning of the next end step.

Equipped creature gets +2/+2.
Whenever equipped creature attacks, draw a card. Noncreature spells you cast this turn can be cast as though they had flash.
Equip {2}

{T}: Add {C}.
{3}, Discard Ancient Ossuary: Search your library for a land card, reveal it, put it into your hand, then shuffle.

Enchant creature
Embody (Enchanted creature is a copy of this card except for its types.)
As long as Legend of the Brave is tapped, you may have creatures you control assign their combat damage as though they weren't blocked.

Protection from multicolored
[+2]: Create a colorless artifact token named Mind Stone with “{T}: Add {C}” and “{1}, {T}, Sacrifice Mind Stone: Draw a card.”
[–3]: Create Barxbot 9000, a legendary 6/4 colorless Construct artifact creature token with “All damage that would be dealt to Barx planeswalkers you control is dealt to this creature instead.”
[–12]: You and target opponent each gain control of each permanent the other controls that's one or more colors.

Flying
When Glenach enters, put three -1/-1 counters on a creature you control.
When Glenach leaves the battlefield, return target non-Insect permanent card from your graveyard to your hand.

Foretell {2}{U}{U} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)
Choose one. If this spell was foretold, you may choose both instead —
• Draw three cards, then discard two cards.
• The owner of target nonland permanent puts it on the top or bottom of their library.

Counter target spell. If a noncreature spell is countered this way, conjure a card named Fatigue and put it on top of your library. (It's a colorless sorcery that costs {2} with “Draw a card.”)

Trample
Lumbering Ox gets +1/+1 for each land you control.
At the beginning of your upkeep, reveal the top card of your library. If it's a land card, you may exile it and repeat this process.
You may play cards exiled with Lumbering Ox.

Enchant player
At the beginning of enchanted player's upkeep, if they control two or more creatures and/or planeswalkers, they sacrifice a creature or planeswalker.

[+1]: Each player discards a card or sacrifices a creature.
[–3]: Vikalden deals X damage to any target and you gain X life, where X is the number of Swamps you control.
[–5]: You get an emblem with “{B}, Pay 2 life: Draw a card.”

When Lifegorging Aberration enters, each opponent loses X life, where X is the number of Zombies you control. You gain life equal to the life lost this way.

Trample
{T}, Sacrifice another creature: You gain 3 life.
Whenever another creature you control dies, put a +1/+1 counter on Bloodbriar Archdruid.

Lifelink
When Hyctaleon's Vanguard enters, look at the top six cards of your library. You may put a Soldier card with lesser mana value from among them onto the battlefield. Put the rest on the bottom of your library in a random order.
Other Soldiers you control get +1/+1.

Double strike
When this creature enters, mill four cards. Put a creature card with power 2 or less from among the cards milled this way into your hand.

Whenever Mukal Sire or another Construct you control enters, Mukal Sire deals 1 damage to each opponent.
Respawn (When this creature dies, if it attacked this turn, return it to its owner's hand.)

Concord — {1}{G}: Until end of turn, Seadrake Rider gets +2/+3 and must be blocked if able. Activate only during your turn, only once each turn, and only if there are four or more card types among permanents you control.

({T}: Add {G}.)
Wanderlust — Otherworldly Forest enters tapped unless you control four or more other differently named lands.
{1}, {T}: Add one mana of any color.

Forgotten Attic enters tapped.
When Forgotten Attic enters, look at the top card of your library. You may put it into your graveyard.
{T}: Add {U} or {B}.

If you would create an Army token while Mehr's Unending Horde is in your graveyard, you may instead return Mehr's Unending Horde from your graveyard to the battlefield.
Counters remain on Mehr's Unending Horde as it moves to any zone other than a player's hand or library.

Add three mana of any one color.

Whenever you cast a spell, harmonize. (Trigger up to one harmony of a permanent you control.)
Harmony — Target permanent you control becomes a 2/2 creature with flying in addition to its other types until end of turn.

Flying
When Nizev Arbiter enters, judge another target creature you control. (Honor it by putting a +1/+1 counter on it or condemn it by sacrificing it to draw a card.)