msem-instigator

Deception {1}{B} ({1}{B}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
When Aguri, Shadow of Doubt enters the battlefield, target player reveals their hand. You choose a nonland card from it. That player discards that card. You lose 2 life.

If a player would draw a card, instead that player may put a card they own exiled with Arroyo, the Bound into their hand.
{3}: Search target player's library for a card and exile it face down, then that player shuffles. They may look at that card for as long as it remains exiled.

Each other colorless creature you control enters the battlefield with an additional +1/+1 counter on it.

Menace
Whenever a creature you control deals combat damage to a permanent, that permanent's controller sacrifices it.

Flameblade deals 4 damage to target player or planeswalker.

Enchant player
At the beginning of enchanted player's upkeep, that player chooses draw step, main phase, or combat phase. They skip each instance of the chosen step or phase this turn.

Target player can't cast spells this turn.
Fabled {2}{W}{U} (Then if you cast this for its fabled cost, put it onto the battlefield transformed attached to that player.)

[+2]: Exile the top two cards of your library. You may put a permanent card from among them into your hand.
[–3]: Create Salim, a legendary 3/3 green and white Cat creature token with vigilance, trample, and indestructible.
[–3]: You get an emblem with “Whenever a creature enters the battlefield under your control, that creature gets +2/+2 and gains haste until end of turn.”

When Sundering Arcanist enters the battlefield, you may destroy target artifact or enchantment.
If you would draw a card, you may sacrifice a land and mill four cards instead. If you do, return Sundering Arcanist from your graveyard to your hand.

{T}: Add {C}.
{1}: Tomb of Shifting Sands becomes a copy of target land card in any graveyard, except it has this ability and it's a Desert in addition to its other types. (This effect lasts indefinitely.)

Whenever one or more creatures attack you or a planeswalker you control, reveal the top card of your library, then put a -1/-1 counter on each attacking creature with the same mana value as the revealed card.