mtg double faced cards The Mechanics of Modern Horizons 3: Modal Double-Faced DDR#907 - Shiko, Paragon of
Description
The Courts Monarch is a mechanic that doesnt exist in a game of Commander until someone plays a card that introduces it

Proxy cards are not allowed generally but in certain conditions, it is allowed to include a proxy card in the deck of a player for a specific game by the judges making it an official proxy

It was perceived as the worst color at ramping and drawing, making mono-white a brave choice for any Commander player

The prices change a lot, ranging from a couple of dollars to thousands depending on the card, the condition, the set, etc
98 additionalMagic: The Gatheringcards

This makes them great choices for questing, as its much harder to remove them from play
