msem-instigator

At the beginning of each opponent's upkeep, if that player has no cards in their hand, Cage of Torment deals 2 damage to that player.

[+1]: Create a 1/1 blue Dragon creature token with flying and “This creature can't attack unless you control a nontoken Dragon.”
[–2]: Flynn deals damage to target creature or planeswalker equal to the total power of Dragons you control.
[–5]: You get an emblem with “Dragon spells you cast cost {U}{R} less to cast and have flash.”

Choose one —
• Search your library for a card with harmony, reveal it, put it into your hand, then shuffle.
• Harmonize twice. (To harmonize, trigger up to one harmony of a permanent you control.)

Hexproof
When Elusive Devout enters, choose one —
• Put a +1/+1 counter on Elusive Devout.
• Create a colorless artifact token named Lotus Petal with “{T}, Sacrifice this artifact: Add one mana of any color.”

[+2]: Target player exiles a card from their hand at random. Until the end of that player's next turn, they may play that card.
[0]: Gain control of target creature or planeswalker until end of turn. Tap it.
[–9]: Take an extra turn after this one. During that turn, you control all opponents.

Infamy 1 (Whenever this creature deals combat damage to a player, if it has no +1/+1 counters on it, put a +1/+1 counter on it and it becomes infamous.)
When Alpha Scout becomes infamous, create a 2/2 green Wolf creature token.

Whenever you cast a noncreature spell, put a hatch counter on Molten Incubation. Then if it has five hatch counters on it, sacrifice it and choose one —
• Create a 5/5 red Dragon creature token with flying.
• Molten Incubation deals 20 damage to each creature.

Enchant creature you control
Enchanted creature has “{T}: Look at the top two cards of your library. Put one of them into your hand and the other into your graveyard.”
{6}{U}{U}, Exile Perceive Eons from the battlefield or your graveyard: Shuffle your graveyard into your library. Take an extra turn after this one. Activate only as a sorcery.

As an additional cost to cast this spell, discard a card.
Draw two cards. Gift of the Phoenix deals 2 damage to you.

Lifelink (Damage dealt by this creature also causes you to gain that much life.)
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)

{U}: If Engrossed Reader doesn't have flying, put a flying counter on it.
{1}{U}: If Engrossed Reader has flying, draw a card, then discard a card. If you discarded a nonland card, put a +1/+1 counter on Engrossed Reader.
{1}{U}{U}: If Engrossed Reader has a +1/+1 counter on it, it becomes a copy of another target creature until end of turn.

Trample
Ride {3}{G} ({3}{G}: Transform this and attach it to target creature you control without a Steed. Ride only as a sorcery.)

When Spirit of Autumn enters, nourish X, where X is the number of creatures you control. (To nourish X, either put X +1/+1 counters on this creature or create X 1/1 white Citizen creature tokens.)

At the beginning of your upkeep, you may exile a card from your hand. If you do, draw a card.
Whenever equipped creature deals combat damage to a player, you may put a card exiled with Travel Pouch into its owner's hand.
Equip {1}

Target creature gets -3/-3 until end of turn. When that creature dies this turn, its controller loses 2 life.

Flying, haste
Whenever Scourge of the Skies attacks, you may have it deal 5 damage to target creature.

Flying
{1}{U}: Reveal the top card of your library. Moonwing Watcher's base power becomes equal to that card's mana value.
Prophecy {U} (Once each turn, you may exile a card with prophecy as you reveal it. When you do, you may cast it for its prophecy cost as long as it's exiled.)

Create two 1/1 colorless Servo artifact creature tokens.
Leitmotif (If you cast this spell from your hand, exile it as it resolves. When you next cast a spell that shares a color with this card, you may cast this from exile without paying its mana cost.)

Flash
Whenever you cast an artifact or enchantment spell, put a +1/+1 counter on Observer of Secret Paths. It can't be blocked this turn.

Hexproof
Whenever an opponent casts a spell or draws a card, draw a card.

Flying, trample
When Ashen Persecutor enters, target opponent reveals their hand. You choose a nonland card from it. That player discards that card and you gain life equal to its mana value.

Exile the top card of your library and up to one target permanent card from your graveyard. You may play cards exiled this way until the end of your next turn.
You may play an additional land this turn.

Braineater Abominus can't be blocked by creatures with power 4 or greater.
Whenever a creature you control deals combat damage to a player, exile the top card of that player's library. You may play that card for as long as it remains exiled, and you may spend mana as though it were mana of any type to cast it.

Armed — Merciless Brute gets +2/+2 as long as it's equipped.