msem-instigator

Trample
Whenever Heir to the Old Bonds becomes the target of a spell or ability you control for the first time each turn, put a +1/+1 counter on it.

{T}: You may put a land card from your hand onto the battlefield.
{1}, {T}: Aetherize target land you control. (To aetherize, create a token that's a copy of it, then exile that token.)

Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.
Madness {1}{G} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)

Whenever you cast a creature spell or create a creature token, you may exile target creature you control. Return it to the battlefield under its owner's control at the beginning of the next end step.

Melee (Whenever this creature attacks, it gets +1/+1 until end of turn for each opponent you attacked this combat.)

Somberwald Slaughterer can't be blocked by creatures with power 2 or less.
At the beginning of your end step, if Somberwald Slaughterer didn't attack this turn, transform it.

Vigilance

Flash
{U}, Put Elusive Hunter into its owner's library second from the top: Counter up to one target spell unless its controller pays {2}.

Enchant opponent
Creatures enchanted player controls get -2/-2.
Whenever enchanted player casts a noncreature spell, they lose 2 life and you gain 2 life.

This spell can't be countered.
Whenever a creature you control with power 5 or greater attacks alone, it deals damage equal to its power to each opponent and to each other creature and planeswalker.

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.

Untap all permanents you control.
Coalesce {5}{G}{U} (You may cast this from your graveyard for {5}{G}{U}. If you do, it enters as a Horror creature after it resolves. Exile it if it would leave the battlefield or not resolve.)
{G}{U}: Untap Fulfill Twisted Dreams.

Enchant creature
{U}: Tap enchanted creature.
{1}{U}: Untap enchanted creature and gain control of it until end of turn.

Menace
{3}{B}, Discard a card: Unhallowed Singers gets +3/+0 until end of turn. Whenever it deals combat damage to a player this turn, they discard a card.

When this creature enters, target creature seeks secrets. (Give it that Oath Aura. Fulfill it by attacking with it and two or more other creatures to draw a card.)
Whenever you draw a card, each opponent loses 1 life and you gain 1 life.

Flash
Flying

Scry 1, then you draw a card and you lose 1 life.

({T}: Add {B} or {R}.)
Fiery Chasm enters tapped.

Vigilance
When Terror of the Ulvenwald enters, target creature gets +3/+3 until end of turn.
Forestcycling {2} ({2}, Discard this card: Search your library for a Forest card, reveal it, put it into your hand, then shuffle.)

Gruff Clutch enters with six +1/+1 counters on it.
{R}, Remove a +1/+1 counter from Gruff Clutch: It deals 1 damage to any target.

Flying, first strike
If one or more tokens would be created under your control, those tokens plus a 1/1 black and red Vampire creature token with menace are created instead.
{3}{B}{B}: Each opponent loses X life and you gain X life, where X is the number of Vampires you control.

Concord — Whenever Chitinborn Sentry attacks, if there are four or more card types among permanents you control, prevent all damage that would be dealt to target attacking creature this turn.

This spell costs {1} less to cast for each enchantment you control.
Destroy all creatures.

When Ethersketch Blueprints enters, create a 1/1 blue Thopter artifact creature token with flying.
{2}, Sacrifice Ethersketch Blueprints: Draw a card.
Monument {5}{B}{B} (You may cast this transformed from your graveyard for its monument cost. Exile it if it would leave the battlefield or not resolve.)
Ascend {4}{W} ({4}{W}: Exile this permanent, then return it to the battlefield transformed. Ascend only as a sorcery.)

If a creature entering the battlefield under your control causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.
{1}{U}, {T}: Exile another target creature. Return it to the battlefield under its owner's control at the beginning of the next end step.