Magic: The Gathering Archenemy

Archenemy is a multiplayer format where one player is selected to be the "archenemy", and the rest of the players play against them. Players start normally at 20 life, but the archenemy starts at 40 life, plays first, and draws a card on their first turn. In addition to their normal library of Magic cards, the archenemy starts with a shuffled deck of at least 20 scheme cards where there are no more than 2 copies of any individual scheme card. Right before the beginning of the archenemy's first main phase, the archenemy draws the top card of their scheme deck and resolves the card, puts it on the bottom of the scheme deck, and then proceeds with their turn normally. The archenemy's opponents share their turn steps (i.e. they occur at the same time) but do not share cards, life totals, mana pools or any other resource, similar to Two-Headed Giant. The archenemy wins by defeating each of their opponents by the normal means, but their opponents all win if they are defeated.

There are currently 65 schemes, with 5 additional promotional schemes ("Perhaps You've Met My Cohort", "Plots That Span Centuries", "Your Inescapable Doom", "Imprison This Insolent Wretch" and "Drench the Soil in Their Blood") released, with the possibility of more being added in the future similarly to the manner in which Planechase has been supported. Some schemes are "Ongoing Schemes" and remain in play until a certain condition is met such as a creature entering a graveyard (e.g. "My Undead Horde Awakens"). Other schemes allow an archenemy to target an opponent (e.g. "Behold the Power of Destruction"), and some of those give the target opponent the option of being the sole player disadvantaged by that scheme or to have every opponent be targeted by a lesser disadvantage (e.g. "May Civilization Collapse").

• Archenemy Rules Revealed
• Archenemy product page