msem-instigator

Lifelink
Sacrifice Devoted Apothecary: Remove a counter from target permanent.

Put three -1/-1 counters on target attacking or blocking creature.

Distribute four -1/-1 counters among any number of target attacking or blocking creatures.

Reach
As Celestial Principality enters, choose a number.
Noncreature spells with mana value equal to the chosen number can't be cast.

Flash
Creatures you control get +1/+1.

Choose one —
• Destroy all creatures.
• Create a 4/4 white Angel creature token with flying and vigilance.

When Broken Spirit enters, exile target creature an opponent controls until Broken Spirit leaves the battlefield.
Persist (When this creature dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

Your opponents can't cast spells or activate abilities that aren't mana abilities this turn.

Flying, vigilance

Activated abilities of sources you don't control can't be activated unless they're mana abilities.

As The Mistake enters, choose a card name.
Activated abilities of sources with the chosen name can't be activated unless they're mana abilities.
Unveil {5} ({5}: Transform this. Unveil only as a sorcery.)

Flying, haste
Whenever Pyrus, the Undying Flame attacks, add {R}{R}{R}{R}. You don't lose this mana as steps, phases, and turns end.
{1}{R}: Pyrus gets +1/+0 until end of turn.

{1}{R}: Performer of Desire gets +1/+1 and gains menace until end of turn. Then if its power is 4 or greater, you may transform it.

[+1]: Tap up to one target creature. It doesn't untap during its controller's next untap step.
[–2]: Exile target card from a graveyard. Create a 2/2 blue and black Elemental creature token.
[–7]: You get an emblem with “You may play cards from exile.”

{U}{B}, {T}: Draw a card, then each player exiles the top card of their library. Then if a player owns two or more cards exiled with Arina, Volarian Explorer, exile her, then return her to the battlefield transformed under her owner's control.

{T}, Pay 1 life, Sacrifice Wayfarer's Shrine: Search your library for a basic land card, put it onto the battlefield, then shuffle.

{T}: Add {C}.
{1}, {T}, Sacrifice War-Torn Tundra: Arm target creature you control. Activate only as a sorcery. (Create a colorless Equipment artifact token with “Equipped creature gets +1/+0” and equip {2}, then attach it to that creature.)

Raider's Den enters tapped.
{T}: Add {R}.
{R}, {T}: Target creature you control gains menace until end of turn. Activate only as a sorcery and only if you control a red creature.

{T}: Add {C}.
{2}, {T}: Prevent all combat damage target creature would deal this turn.

Hibernation Den enters tapped.
{T}: Add {W}.
{W}, {T}: You gain 1 life. Activate only as a sorcery and only if you control a white creature.

Greenheart Den enters tapped.
{T}: Add {G}.
{G}, {T}: Target creature you control gets +1/+1 until end of turn. Activate only as a sorcery and only if you control a green creature.

Dragon Queen's Den enters tapped.
{T}: Add {U}.
{U}, {T}: Scry 1. Activate only as a sorcery and only if you control a blue creature.

Abandoned Den enters tapped.
{T}: Add {B}.
{B}, {T}: Target player loses 1 life. Activate only as a sorcery and only if you control a black creature.

Whenever Weathered Skiff attacks, it gets +1/+1 until end of turn.
Crew 2 (Tap any number of creatures you control with total power 2 or greater: This Ship Vehicle becomes an artifact creature until end of turn.)

When Viking Greataxe enters, attach it to target creature you control.
Equipped creature gets +2/+1.
Equip {3}