Advocate of the Outlands
Creature — Human Rebel
Companion — You start the game with an emblem with "You can't become the monarch."
Whenever an opponent draws a card except during their draw step, you draw a card.
2/2

Advocate of the Custodi
Creature - Spirit Advisor
Companion - You start the game with an emblem with "You can't become the monarch."
The monarch plays with their hand revealed.
Flying, Ward
"As you held Brago to such high standards, so shall we hold you, Marchesa."

Whisperer Behind the Throne
Creature — Human Advisor
Menace
Whenever you draw a card, reveal it and the monarch loses life equal to that card's mana value.
2/1

Advocate of the Prisoners
Creature — Goblin Rebel
Companion — You start the game with an emblem with "You can't become the monarch."
Menace
Whenever Advocate of the Prisoners deals combat damage to the monarch, you may have another opponent become the monarch.
Whenever an opponent becomes the monarch, exile the bottom card of their library. Until the beginning of your next end step, you may play that card.
3/3

You guys obviously know the planes much better than I. I have no idea which one we are currently on.

Fiora, home of the Conspiracy sets.

Advocate of the Wilds
Creature — Human Druid Rebel
Companion — You start the game with an emblem with "You can't become the monarch."
Vigilance
Whenever a creature attacks, if it's attacking the monarch, it gets +1/+1 and gains trample until end of turn.
2/3

Cultivator of Cruel Aspirations
Creature — Human Advisor
As you draft this card, secretly choose a card name.
When Cultivator of Cruel Aspirations enters the battlefield, choose target creature you don't control. You may reveal the chosen card name. If you do and that creature has that name, you gain control of it. Otherwise, return that creature to its owner's hand and its controller discards a card.
2/2

Marchesa's Ancestral Cloak —
Legendary Artifact — Equipment (M)
Channel — , Discard Marchesa's Ancestral Cloak: Target player discards a card and loses 1 life. Activate only as a sorcery.
Equipped creature gets +1/+0.
If equipped creature would die, you may sacrifice Marchesa's Ancestral Cloak and regenerate equipped creature instead.
Pay 13 life, exile Marchesa's Ancestral Cloak from your graveyard: You can't lose the game and your opponents can't win the game this turn.
Equip

Parliamentarians' Chamber
Land (R)
Draft this card face up.
Instead of drafting a card from a booster pack, you may remove that card from the draft and note its colours.
: Add one mana of any colour noted for cards you drafted named Parliamentarians' Chamber.

Next is Eldraine.

Promise of Reciprocity
Enchantment
When Promise of Reciprocity enters the battlefield, you may have you and target opponent each draw a card. If you do, put an obligation counter on Promise of Reciprocity.
Whenever an opponent draws their second card each turn, put an obligation counter on Promise of Reciprocity unless that player has you draw a card.
, Remove X obligation counters from Promise of Reciprocity and sacrifice it: Create X 2/2 white Knight creature tokens with vigilance. Activate this ability only as a sorcery.
"My duty is in the Wilds. Your duty is at the castle walls. There is no greater glory than our shared duty and assurance."

Brilliant Destiny —
Enchantment — Aura (R)
Enchant Role
Enchanted Role and the creature it enchants have Ward , where X is the number of prophecy counters on it.
At the beginning of your upkeep, put a prophecy counter on enchanted Role. Then, if it has five or more prophecy counters, you win the game.

The Beheading Game
Enchantment
At the beginning of your end step, you may sacrifice a creature. If you do, target opponent sacrifices a creature. If the creature you sacrificed has a greater mana value than the creature that player sacrificed, that player loses life equal to the difference and you draw a card. If the creature you sacrificed has a lesser mana value than the creature that player sacrificed, that player gains life equal to the difference.

Witch's Herb-Trance —
Sorcery (C)
Create a Wicked Role token attached to target creature you control. Exile the top two cards of your library. You may cast them so long as you control an enchanted creature.
"Terrible headaches, and terrible news. I don't know why I bother with these rituals."
—Eriette

Challenger of the Wilds
Legendary Creature — Elemental Knight
Vigilance
When Challenger of the Wilds enters the battlefield, if it was cast, target opponent chooses a creature they control. That creature fights Knight of the Wilds. When Challenger of the Wilds dies this turn, return it to the battlefield with X +1/+1 counters on it, where X is the damage dealt to it this turn.
4/4

Girdle of Protection
Artifact — Equipment
Equipped creature isn't a Knight and can't become a Knight.
, : Equipped creature gains indestructible until end of turn. Tap it. Remove it from combat. If it was blocking one or more creatures, those creatures gain trample until end of turn.
Equip
Persistence without love is obsession. Courage without fear is ignorance. Strength without gentleness is brutality.

The Green Chapel
Legendary Land
The Green Chapel enters the battlefield tapped.
: Add .
, , Sacrifice an artifact or enchantment or token: Create The Green Knight, a legendary 4/4 green Elemental Knight creature token. Activate this ability only if you don't control a creature named The Green Knight.

Next is Ikoria.

Flickerhound
Creature - Dog Lizard (R)
Flash
You may mutate ~ as an instant.
Whenever ~ mutates, you may exile it. If you do, return it to the battlefield tapped at end of turn.
Mutate
[3/2]

Having flash already lets you mutate instantly; mutate is an alternate casting cost, e.g., Pouncing Shoreshark. Also, flickering a mutated creature means they all come back as separate creatures. Not sure if you intended that.

Storm Stag
Creature — Elemental Elk
Prowess
Mutate
Noncreature spells you cast cost less to cast for each time this creature has mutated.
2/2

Huh I did not intend for that tbh. Would try phasing instead then. Just didn't because it is more of blue s thing.

Flawed Adaptation
Sorcery
Destroy target mutated creature.
Survival of the fittest means little if survival was guaranteed.