msem-instigator

You may have Darksteel Mirror enter as a copy of any permanent on the battlefield, except it has indestructible in addition to its other abilities.

Menace
Pay 2 life: Investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)
Sacrifice a permanent: Darna gets +1/+1 until end of turn.

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
Whenever a creature an opponent controls dies, its controller discards a card and loses 1 life.
{1}{B}{B}, {T}, Sacrifice another creature: Destroy target creature.

Flying (This creature can't be blocked except by creatures with flying or reach.)
Whenever a creature you don't control blocks, it gets -1/-0 until end of turn.

When Dazzling Festivities enters or at the beginning of your upkeep, you may have each player reveal the top card of their library. Starting with you, each player may cast a nonland card revealed this way without paying its mana cost.

Destroy all creatures.
Kindle X—{X}, Exile a card with mana value X from your graveyard. ({X}, Exile a card with mana value X and this card from your graveyard: Create X 1/1 colorless Elemental creature tokens. Kindle only as a sorcery.)

Destroy target creature. You may put a -1/-1 counter on target creature.

Each opponent sacrifices a creature, then loses 4 life. You return a creature card from your graveyard to your hand, then gain 4 life.

Return target creature card from your graveyard to the battlefield. If this spell was cast from a graveyard, you lose life equal to that creature's mana value.
Flashback {1}{B}{B} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Enchant creature
When Deathless Conscription enters, untap enchanted creature.
You control enchanted creature.

Decay deals damage to creatures in the form of -1/-1 counters.
{B}{G}: Until end of turn, target creature deals damage to creatures in the form of -1/-1 counters. Activate only if Decay is in your graveyard.

Deception can't be blocked.
{1}{U}{B}: Target creature can't be blocked this turn. Activate only if Deception is in your graveyard.

Creatures you control get +2/+2 and gain vigilance and trample until end of turn.

When Decrepit Hero dies, create a 2/2 black Soldier creature token.
Fleeting {1}{B} (You may cast this spell for its fleeting cost. If you do, sacrifice it at the beginning of the next end step.)

Deep-Sea Terror can't attack unless seven or more cards are in your graveyard.

Damage dealt by Deepwater Stinger can't be prevented.

Search target opponent's library for a card and exile it, then do the same for their hand and graveyard. That player shuffles. You may cast spells exiled this way for as long as they remain exiled, and you may spend mana as though it were mana of any color to do so.

When Deliver from Dilapidation enters, you may sacrifice any number of enchantments. Whenever you sacrifice an enchantment this way, destroy target creature.
At the beginning of your upkeep, return target enchantment card with mana value 5 or less from your graveyard to the battlefield.

{1}{B}, Sacrifice another creature: Draw a card and create an Idol token. (It's an artifact with “{1}, Sacrifice this artifact: Put a +1/+1 counter on target creature. Activate only as a sorcery.”)
{2}{B}, Sacrifice three Idols: Return Demon of Hubris from your graveyard to the battlefield. Activate only as a sorcery.

Create a 4/4 black Demon creature token with flying. You lose 3 life for each Demon you control.
Tether (Then if you cast this from your hand, you may exile it tethered to a creature you control. When it dies, you may cast this from exile without paying its mana cost.)

Whenever this creature attacks, if you gained or lost life this turn, it gains flying until end of turn.
When this creature dies, create a 2/2 black Zombie creature token.

Flash

Trample
When Depthlight Frontliner enters, you may salvage up to one instant card and up to one sorcery card. (Exile those cards from your graveyard until this creature leaves the battlefield. Whenever this creature deals combat damage to a player, put a card it salvaged into your hand.)

Frenzy 3 (Whenever this creature attacks and isn't blocked, it gets +3/+0 until end of turn.)
Other red creatures you control have frenzy 2. (If a creature has multiple instances of frenzy, each triggers separately.)
Other creatures you control have frenzy 1.

This spell costs {1} less to cast for each card you've drawn this turn.
Return up to two target creatures with total mana value 5 or less from your graveyard to the battlefield.