msem-instigator

When Ruler of Cities enters, you may search your library for an Aura that could enchant a land you control, reveal it, put it into your hand, then shuffle.
Whenever an Aura becomes attached to a land you control, you gain 2 life.

Whenever a creature you control enters, you may have it deal damage equal to its power to another target creature or planeswalker.
I, II, III — Exile the top two cards of your library. You may put a creature card from among them onto the battlefield with a +1/+1 counter on it. It gains haste.
IV — Creatures you control get +3/+3 and gain trample until end of turn.

Target opponent sacrifices a creature. Create an X/X black Zombie creature token, where X is the sacrificed creature's power.

Whenever a creature or planeswalker enters under an opponent's control, sacrifice Rune-Scribe's Trap unless you pay {R}. If you sacrifice it, it deals 6 damage to that permanent.

You may spend mana as though it were mana of any color to cast spells with mana value 5 or greater or to activate abilities of permanents or permanent cards with mana value 5 or greater.
{T}: Add {C}.

{T}: Add {C}.
{4}, {T}: Look at the top two cards of your library. You may put one of them into your graveyard. Put the rest back on top in any order. If you control eight or more lands, draw a card.

Enchant land
Whenever enchanted land becomes tapped, scry 1.
Enchanted land has “{G}, {T}: Each player reveals the top card of their library. Each player that revealed a land card this way may put that card into their hand.”

Equipped creature can't be blocked except by enchantment creatures.
Whenever equipped creature deals combat damage to a player, you may search your library for a card, exile it, then shuffle. If you don't search your library this way, you may play a card exiled with Runner's Harness.
Equip {1}

Rushing Waters enters tapped.
{T}: Add {U} or {R}.
When Rushing Waters enters, you may put a loyalty counter on a planeswalker you control.

Improve {1}{U} ({1}{U}: Put a +1/+1 counter on this creature. This costs {1} more to activate for each +1/+1 counter on it. Improve only as a sorcery.)
At the beginning of your end step, if one or more embattled creatures you controlled dealt damage to a player, you may draw a card. (A creature is embattled if it has a counter on it or has a permanent you control attached to it.)

Rustshell Crustacean gets +1/+1 for each artifact you control.
Whenever Rustshell Crustacean attacks, choose one —
• Search your library for an Equipment card, reveal it, and put it into your hand, then shuffle.
• Create a Treasure token.

Whenever Rustshell Mantis is dealt damage, put that many +1/+1 counters on it. (It must survive the damage to get the counters.)

Target creature gains trample until end of turn. The next time a source of your choice would deal damage to that creature, prevent that damage. If damage is prevented this way, that creature gets +X/+0 until end of turn, where X is the amount of damage prevented this way.

Whenever you cast a spell that's red, green, white, or blue, each opponent loses 1 life and you gain 1 life.

Whenever another creature you control dies, put a +1/+1 counter on Ruthless Weichafe and you lose 1 life.
Whenever Ruthless Weichafe attacks, if its power is 4 or greater, it gains lifelink until end of turn.

Haste
Whenever an embattled creature you control deals combat damage to a player, you may pay {2}{G}. If you do, create a token that's a copy of that creature, except the token isn't legendary if the creature is legendary. (A creature is embattled if it has a counter on it or has a permanent you control attached to it.)

Whenever S-40 Wallbreaker attacks, create a 1/1 colorless Construct artifact creature token.
{X}, Sacrifice X artifacts: S-40 Wallbreaker deals X damage to each opponent.

Equipped creature gets +2/+0 and can't be blocked.
Whenever a Rogue you control attacks, you may pay {1}. If you do, attach Saber of Defiled Rites to it.
Equip {5}

Spells you cast during combat cost {1} less to cast.
Spells your opponents cast during combat cost {1} more to cast.

Trample
Each opponent can cast spells only any time they could cast a sorcery.
Auras you control attached to other permanents you control also enchant Sacred Lynx if able.

Once each turn, when you activate a nonmana ability, you may put a stage counter on Sacred Opus.
{1}{W}: Until end of turn, Sacred Opus becomes an Angel Avatar creature in addition to its other types and gains “This creature's power and toughness are each equal to the number of stage counters on it.”

({T}: Add {W}.)
Sacred Sanctuary enters tapped with two sanctum counters on it.
{T}, Remove a sanctum counter from Sacred Sanctuary: Add {G} or {U}.

{G}: Exile target card from a graveyard. If it was a land card, put a +1/+1 counter on Sacrificial Bull.
{G}, Sacrifice Sacrificial Bull: You gain life equal to its power.

When Saddled Scuttleback enters, you may search your library for a Crab, Fish, Jellyfish, Kraken, Leviathan, Merfolk, Nautilus, Octopus, Otter, Oyster, Pirate, Seal, Serpent, Shark, Shrimp, Sponge, Squid, Starfish, Trilobite, Turtle, Whale, or Island card, reveal it, put it into your hand, then shuffle.

Vigilance
Whenever Saeedi Kahroba, Daughter attacks, recruit. (Create a 0/0 white Soldier Army creature token, then put a +1/+1 counter on each Army you control.)