When a player faces a villainous choice, they first choose one of the two options, then all actions in the chosen option are performed.

Each creature turned face down this way or put onto the battlefield this way is a 2/2 Cyberman artifact creature with no name and no color.

If, for any reason, the face-down creature is turned face up, the effect making it a Cyberman ends. It will be whatever is printed on the card.

The player who controls a face-down permanent may look at it at any time. Notably, if the cards were put on the battlefield face down from another player's library, the player that owns them does not get to look at those cards.

Double-faced permanents that are already on the battlefield can't be turned face down this way. However, a double-faced card can be put onto the battlefield face down from another zone this way.

If the face-down card has a morph ability, its controller may turn it face up by paying the associated morph cost.

If a spell or ability requires multiple players to face a villainous choice, the result is a little different from other effects in Magic. In that case, the first player in turn order makes their choice and the action for that choice is performed before the next player makes their choice. Then each of the remaining players repeat this process in turn order.

A player facing a villainous choice can always choose either option, even if one or both of the options are impossible. For example, if one of the options is to sacrifice a creature, a player who controls no creatures can still choose that option.

Missy : règles, fonctionnement et interactions (MTG)

Missy is one of those cards players keep asking about. Here is, in plain words, what its official text says, the rulings published by Wizards of the Coast, and the combos players actually run.

Official card text

Whenever another nonartifact creature dies, return it to the battlefield under your control face down and tapped. It's a 2/2 Cyberman artifact creature. At the beginning of your end step, each opponent faces a villainous choice — Each artifact creature you control deals 1 damage to that opponent, or you draw a card and chaos ensues.

How it works : Missy

Original English text — Wizards of the Coast / Scryfall

#1October 13, 2023· Wizards of the Coast
When a player faces a villainous choice, they first choose one of the two options, then all actions in the chosen option are performed.
No other card is named in this ruling.
#2October 13, 2023· Wizards of the Coast
Each creature turned face down this way or put onto the battlefield this way is a 2/2 Cyberman artifact creature with no name and no color.
Card named in this ruling
Cyberman
#3October 13, 2023· Wizards of the Coast
If, for any reason, the face-down creature is turned face up, the effect making it a Cyberman ends. It will be whatever is printed on the card.
Card named in this ruling
Cyberman
#4October 13, 2023· Wizards of the Coast
The player who controls a face-down permanent may look at it at any time. Notably, if the cards were put on the battlefield face down from another player's library, the player that owns them does not get to look at those cards.
No other card is named in this ruling.
#5October 13, 2023· Wizards of the Coast
Double-faced permanents that are already on the battlefield can't be turned face down this way. However, a double-faced card can be put onto the battlefield face down from another zone this way.
No other card is named in this ruling.
#6October 13, 2023· Wizards of the Coast
If the face-down card has a morph ability, its controller may turn it face up by paying the associated morph cost.
No other card is named in this ruling.
#7October 13, 2023· Wizards of the Coast
If a spell or ability requires multiple players to face a villainous choice, the result is a little different from other effects in Magic. In that case, the first player in turn order makes their choice and the action for that choice is performed before the next player makes their choice. Then each of the remaining players repeat this process in turn order.
No other card is named in this ruling.
#8October 13, 2023· Wizards of the Coast
A player facing a villainous choice can always choose either option, even if one or both of the options are impossible. For example, if one of the options is to sacrifice a creature, a player who controls no creatures can still choose that option.
No other card is named in this ruling.
#9October 13, 2023· Wizards of the Coast
Unlike other creature types in Magic that are each only one word, the two words "Time Lord" represent a single creature subtype. Time Lord is the only two-word creature type.
No other card is named in this ruling.
#10October 13, 2023· Wizards of the Coast
Neither "Time" nor "Lord" are creature types. Some older cards were printed with the subtype "Lord," but all of those cards have updated Oracle card text that removed that type.
No other card is named in this ruling.
#11October 13, 2023· Wizards of the Coast
If an effect instructs you to choose a creature type, you may choose Time Lord.
No other card is named in this ruling.