msem-instigator

Reverberate {2} (When you cast this spell, copy it if you paid its reverberate cost.)
Draw a card.

Counter target spell. If a noncreature spell is countered this way, scry 2.

Renown 1 (When this creature deals combat damage to a player, if it isn't renowned, put a +1/+1 counter on it and it becomes renowned.)
Rafter Stalker can't be blocked by creatures with greater power.

Flash
When Rahit's Prodigy enters, return target instant or sorcery card from your graveyard to your hand, then discard a card.

Archive 5 (As this enters, shuffle the top five cards of your main library into a new face up library. Sacrifice this after the archived library is empty.)
At the beginning of your upkeep, put the top card of any of your libraries on the bottom of the archived library, then you may put any card in the archived library on top of the archived library.

[+1]: For each player, exile the top three cards of that player's library, then put one of those cards into that player's hand.
[0]: Choose target card exiled by Rahit. Until your next turn, you may play that card, and you may spend mana as though it was mana of any type to cast it.
[–7]: Target player draws seven cards.

[+1]: Each player may draw a card. For each opponent who does, put a loyalty counter on Rahit.
[–1]: Each player draws three cards, then puts two cards from their hand on top of their library in any order.
[–6]: You get an emblem with “Discard a card with mana value X: Counter target spell with mana value X or less.”

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

(Add a quest counter as this enters. Sacrifice after 3.)
Whenever you attack, add a quest counter.
1, 2 — Scry 1.
3 — Draw two cards.
​

Raintouched Basin enters tapped.
{T}: Add {U}.
Desertcycling {1}{U} ({1}{U}, Discard this card: Search your library for a Desert card, reveal it, and put it into your hand, then shuffle.)

{T}: Look at the top card of your library. If its mana value is equal to the number of lands you control, you may reveal it and draw a card.
{1}, Return a land you control to its owner's hand: Scry 1.

Art of war — At the beginning of your end step, if Raiun Bay Scourge dealt damage to an opponent this turn, gain control of target artifact or enchantment until Raiun Bay Scourge leaves the battlefield.

Deception {2}{U}{U} ({2}{U}{U}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
Whenever Raloran Insurgent deals combat damage to a player, abound. (You may cast a spell that costs less than this from your hand without paying its mana cost.)

Enchant opponent
When Ranidaphobia enters, create a 1/1 blue Frog creature token.
Creatures enchanted player controls can't block Frogs.

Choose a Function added to Rapid Recursion. Create a Function token with those effects. (It's an enchantment. As you cast an instant or sorcery spell, sacrifice any number of Functions to add their effects to that spell.)
Draw a card.

Target creature can't be blocked this turn. It explores. (Reveal the top card of your library. Put it into your hand if it's a land. Otherwise, put a +1/+1 counter on that creature, then you may put that card in your graveyard.)

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Infiltrate (Whenever one or more attacking creatures you control aren't blocked, this creature gets +1/+1 until end of turn.)

When Raving Brigand enters, forebode. (Create a tapped colorless Omen artifact token with “{T}, Discard a card, Sacrifice this artifact: Draw a card.”)
Whenever you sacrifice an Omen, target player mills three cards.

Whenever a Survivor you control enters, you may draw a card. If you do, discard a card.

Scry 2, then draw a card. (To scry 2, look at the top two cards of your library, then put any number of them on the bottom of your library and the rest on top in any order.)
Foresee — As you draw Read the Clouds, you may reveal it and pay {1}{U}. When you do, scry 2, then draw a card.

Choose one —
• Draw three cards.
• Return up to two target creatures to their owners' hands.

Scry 2, then draw a card.
If you control a legendary permanent, investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)

When this creature enters, surveil 2.
This creature can't be blocked as long as it has a -1/-1 counter on it.

Put four time counters on target nonland permanent. If it doesn't have vanishing, it gains vanishing. (At the beginning of your upkeep, remove a time counter from that permanent. When the last is removed, sacrifice it.)

As an additional cost to cast Reality Reversal, return X nonland permanents you control to their owners' hands.
Return X plus one target nonland permanents to their owners' hands.