msem-instigator

When Sofia enters, if it wasn't cast from your hand, it gains lifelink and haste until end of turn.
Whenever Sofia deals combat damage to a player, exile the top card of that player's library face down and look at it. After the current turn has ended, you may cast that spell from exile by paying life equal to its mana value rather than paying its mana cost. If you do, the spell is foretold.
Foretell {B}{R/W} (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.)

Solar Flare deals 3 damage to any target. You gain 3 life.

When Solar Pact enters, return up to two cards with different mana values from your graveyard to your hand.
Each player can't draw more than one card each turn.

Menace
Whenever a nontoken Warrior you control dies, create a token that's a copy of it, except it's 1/1.

Creatures can't attack you unless their controller pays {2} for each creature they control that's attacking you.
{3}{W}{U}: Tap target creature and put a +1/+1 counter on Solitary Guardian.

At the beginning of each player's upkeep, that player may pay {2} or 2 life. If they don't, they return a permanent they control to its owner's hand.

Whenever another creature you control enters, target opponent loses 1 life and you gain 1 life.
Sacrifice Somber River Bearer: Creatures you control gain indestructible until end of turn.

Enchant permanent
Enchanted permanent is a land with “{T}: Add {G}{W}{U}” and loses all other card types and abilities.
{1}, Discard Song of Shoals: Add one mana of any color. Scry 1.

Create a 4/4 red Dragon creature token with flying.
Showcase {5}{U}{R} (Then if you cast this for its showcase cost, create a 1/1 red Bard creature token that can't block and exile this. Whenever it attacks, you may cast a free copy of this.)

Gain control of target creature until end of turn. Untap that creature. It gains lifelink and haste until end of turn.

Flying, trample, haste
{W}{U}{B}{R}{G}: Create a token that's a copy of another target creature except it's all colors and has haste.
{W}{U}{B}{R}{G}, Exile Soul of Iscathia from your graveyard: Create a token that's a copy of target creature except it's all colors and has haste.

When Soulcarver enters, destroy up to one target non-Demon creature. If you do, create a 2/2 black Demon creature token and draw a card.

First strike, haste
Whenever Soulflare Nymph deals damage to a creature, exile that creature.

Flash
Other Rogues you control get +1/+1.
Rogue spells you cast have flash.

Prowess, trample
During your turn, each instant and sorcery card in your graveyard has flashback. The flashback cost is equal to that card's mana cost plus “Pay X life, where X is this card's mana value.”

Source Decay deals 2 damage to each opponent. Create two 1/1 colorless Servo artifact creature tokens.
Whenever a creature you control deals combat damage to a player, you may pay {2}{B}{R} and sacrifice it. If you do, return Source Decay from your graveyard to your hand.

Spark New Life deals X damage to any target. You may put up to X land cards from your hand and/or graveyard onto the battlefield.

At the beginning of your end step, you may put a progress counter on Sparkline Harness.
[progress 1-3] Whenever an artifact creature you control attacks, it deals 1 damage to target opponent.
[progress 4+] Whenever a creature you control attacks, it deals 1 damage to target opponent.
Whenever a creature you control attacks, it deals 1 damage to target opponent.

Flying, haste
Whenever Spawn of Hadak attacks, draw a card, then discard a card.

Each creature you control that has been dealt damage this turn by a source you controlled has indestructible.

When Speaker of Open Waters enters, create a green and white Aura enchantment token named Moray's Resolve attached to target creature you control. The token has enchant creature and “Enchanted creatures you control get +2/+2 and have trample and lifelink.”

When you cast this spell, create a token that's a copy of it.
Equipped creature gets +2/+2.
Equip {2}

Speckled Outcast has menace as long as it's enchanted.

Flying
{2}, Exile an instant or sorcery card from your graveyard: Spellbone Screecher deals 1 damage to any target.

Hexproof
Creatures you control get +1/+1 for each Aura attached to them.