msem-instigator

Doom deals 3 damage to any target and you gain 3 life.
Reconstruct {3}{B}{B} (You may cast this from your graveyard for its reconstruct cost reduced by the mana value of a permanent you sacrifice as you cast it this way. Then exile this.)
You may cast Doom from exile by paying {4}{B}{B}{B} rather than its mana cost. If you do, shuffle it into your library instead of putting it anywhere else as it resolves.

Look at the top five cards of your library. You may reveal a nonland card from among them. If you do, put that card into your hand and cast a copy of it without paying its mana cost. Put the rest into your graveyard.

Adorned — Mercenary Lancer gets +2/+2 as long as it's equipped and/or enchanted.

When Aether Road Caravan enters, gain control of target nonland permanent with mana value 3 or less for as long as you control Aether Road Caravan.

Crew 1 (Tap any number of creatures you control with total power 1 or greater: This Vehicle becomes an artifact creature until end of turn.)
Whenever Scavengermobile deals combat damage to a player, choose land or nonland, then rediscover a card of that kind. (Look at the top card of your library. You may reveal it and put it into your hand if it's a card of the chosen type. Otherwise, put it back or into your graveyard.)

Each player chooses up to one permanent they control of each permanent type, then sacrifices the rest. (The permanent types are artifact, creature, enchantment, land, and planeswalker.)

Crystal Garden enters tapped.
{T}: Add one mana of any color. You can't spend this mana to cast a creature spell.

Landfall — Whenever a land you control enters, Duskwood Vanguard gets +1/+1 until end of turn.

This spell costs {1} less to cast for each poison counter your opponents have.
Poisonous 1 (Whenever this creature deals combat damage to a player, that player gets a poison counter. A player with ten or more poison counters loses the game.)
At the beginning of your end step, each opponent with seven or more poison counters loses the game.

Enchant creature
Enchanted creature gets +2/+1 and has “Whenever this creature attacks, target creature an opponent controls can't block this turn.”

This spell costs {1} less to cast for each artifact you control. (This applies before Treasures are sacrificed for mana.)
When Underhanded Deal enters, draw three cards.
Whenever you cast a spell, you lose 1 life.

Whenever Stonehoof Familiar is dealt damage, put a +1/+1 counter on it. (It must survive the damage to get the counter.)
Menagerie — As long as there are five or more creature types among creatures you control, all damage that would be dealt to you or other permanents you control is dealt to Stonehoof Familiar instead.

Target player mills two cards. You draw a card and you lose 1 life.
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.)

Prevent all combat damage that would be dealt to and dealt by Bereaved Aristocrat.
Unveil {2}{W}{U} ({2}{W}{U}: Transform this. Unveil only as a sorcery.)

{T}: Add {R}. Put a charge counter on Wistful Automaton.
Remove three charge counters from Wistful Automaton: Transform it.

Flash
When Rahstahde Truthseeker enters, create a Treasure token. (It's an artifact with “{T}, Sacrifice this artifact: Add one mana of any color.”)

This spell costs {1} less to cast for each multicolored card in your graveyard.
Draw four cards.

Flying, haste
Whenever another creature dies, Twinfire Dragon gets +1/+0 until end of turn.

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.

You may look at the top card of your library any time, and you may play Deserts from the top of your library.
[+1]: You gain 1 life. You may discard a card. If you do, draw a card.
[–2]: Sihari deals 2 damage to any target. You may play an additional land this turn.
[–4]: Create an X/X red and green Sand Elemental creature token with trample and haste, where X is the number of lands you control.

Exile target creature you control, then return that card to the battlefield under its owner's control. 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.”)

Target player reveals two cards at random from their hand. You choose one of them. That player discards that card.

Menace
Servitor Vanguard gets +X/+X, where X is the number of other artifacts you control.

Look at the top two cards of target player's library. Put one of those cards on the bottom of their library and the rest on top.
Fuse (You may cast one or both halves of this card from your hand.)

When Hardened Explorer enters, choose one —
• Destroy target artifact.
• Put a +1/+1 counter on Hardened Explorer. It gains haste.