msem-instigator

Target player discards two cards.
Flashback {4}{B} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Destroy up to one target artifact.
Amass Soldiers 2. (Put two +1/+1 counters on an Army you control. It's also a Soldier. If you don't control one, create an 0/0 black Soldier Army creature token first.)

Enchant creature
Enchanted creature gets +2/+2 for each other enchantment you control.

At the beginning of your upkeep, return target enchantment card from your graveyard to your hand.
Whenever Reflect on Serenity or another enchantment you control enters or leaves the battlefield, each opponent loses 1 life and you gain 1 life.

Each creature you control gets +1/+1 for each other creature you control with the same name.

Take an extra turn after this one. If this spell was cast from exile, take two extra turns after this one instead. Shuffle Reflected Moment into its owner's main library.
Prophecy {6}{U}{U} (Once each turn, you may exile a card with prophecy as you reveal it. When you do, you may cast it for its prophecy cost as long as it's exiled.)

Indestructible
When Reflected Worldwalker enters, each player puts their hand into their sideboard.

As Reflective Stalker enters, choose a noncreature card name.
When Reflective Stalker enters, if it was cast, create a token that's a copy of it.
Spells your opponents cast with the chosen name cost {2} more to cast.

Return up to one target artifact card from your graveyard to your hand.
Put the bottom card of your library into your hand.

Each player exiles all permanents they control, draws that many cards, then puts up to that many permanent cards from their hand onto the battlefield. Exile Reform Reality.

Create a token that's a copy of target creature, except it has haste and “At the beginning of the end step, sacrifice this permanent.”
Flashback {1}{G}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Destroy all creatures. If a Reflection would be destroyed this way, its owner shuffles it into their library instead.

Wu Xing (Add effects based on the number of colors of mana spent to cast this spell.)
1 | Refulgent Flare deals 3 damage to any target. If a permanent dealt damage this way would die this turn, exile it instead.
3 | You gain 3 life.

Destroy all monocolored creatures.

Counter target spell.
{1}{U}, Exile Refute from your graveyard: Draw a card.

First strike, trample
Whenever Regal Coralhorn deals combat damage to a player or planeswalker, return target card with a cycling ability from your graveyard to your hand.
Cycling {2} ({2}, Discard this card: Draw a card.)

Each player sacrifices three lands. Regal Ignition deals 3 damage to each nonlegendary creature.

Slipstream (This creature can't be blocked as long as only creatures with slipstream are attacking.)
As long as you control three or more artifacts, Regal Seasnake has vigilance. (Attacking doesn't cause it to tap.)

Instant and sorcery spells you cast cost {1} less to cast.
Whenever you cast an instant or sorcery spell, Regrets of Mortals gets +2/+0 until end of turn. You may discard a card. If you do, draw a card.

Legacy (You may play this side of this card only from your graveyard. Exile it if it would leave the battlefield or not resolve.)
At the beginning of your upkeep, you may return a creature card from your graveyard to your hand. If you do, you gain 2 life.

At the beginning of combat on your turn, you may have Regurgitator Ooze consume. If you do, it gets +2/+2 until end of turn. (To consume, sacrifice another creature or exile a creature card from your graveyard.)
When Regurgitator Ooze dies, return a card exiled with it to its owner's hand.

When Reha, Entropy's Call enters, you may search your library for any number of land cards with different names and exile them with harvest counters, then shuffle.
At the beginning of your upkeep, you may put a card that you own in exile with a harvest counter on it at random onto the battlefield tapped.

Trample
{1}{B}: Rehis-Dorahn Plowbeast gets +1/+1 until end of turn.

If one or more -1/-1 counters would be put on a creature an opponent controls, put twice that many -1/-1 counters on it instead.