Mirror-Style Master

Mana cost: {4}{R}{R}
Type: Creature — Human Warrior
Power / toughness: 3 / 3
Set: March of the Machine Commander #119 (rare)
Price: $0.33 USD

Backup 1 (When this creature enters, put a +1/+1 counter on target creature. If that's another creature, it gains the following ability until end of turn.)
Whenever this creature attacks, for each attacking modified creature you control, create a tapped and attacking token that's a copy of that creature. Exile those tokens at end of combat. (Equipment, Auras you control, and counters are modifications.)

Mirror-Style Master has 2 printings, first in March of the Machine Commander (2023). EDHREC ranks it #12,919 among Commander cards. It appears most in Bright-Palm, Soul Awakener decks (1,423 on EDHREC). 1 public deck on TCG runs it. It has 12 official rulings.

Legality

commander: legal
legacy: legal
vintage: legal
pauper: not legal
modern: not legal
pioneer: not legal
standard: not legal
brawl: not legal

Public decks that run Mirror-Style Master

Call for Backup - March of the Machine Commander, led by Bright-Palm, Soul Awakener

Commanders that run Mirror-Style Master most

Deck counts from EDHREC.

Often played with Mirror-Style Master

Cards that show up in the same decks on EDHREC.

Rulings

2023-04-14: Backup confers only abilities that are actually printed below it. Any abilities that are gained by the permanent are ignored, including abilities gained due to a resolving spell or ability or copy effects.
2023-04-14: If the copied creature has {X} in its mana cost, X is 0.
2023-04-14: If a backup ability targets the creature with backup, that creature will get +1/+1 counters, but it won’t gain additional abilities.
2023-04-14: Although the tokens enter the battlefield attacking, they were never declared as attacking creatures (for the purposes of abilities that trigger whenever a creature attacks, for example).
2023-04-14: If the copied creature is copying something else, then the token enters the battlefield as whatever that creature copied.
2023-04-14: Any enters-the-battlefield abilities of the copied creature will trigger when the token enters the battlefield. Any “as [this creature] enters the battlefield” or “[this creature] enters the battlefield with” abilities of the copied creature will also work.
2023-04-14: If a permanent enters the battlefield as a copy of a card with a backup ability or a token is created that is a copy of that card, the order of the printed abilities is maintained.
2023-04-14: The abilities that backup grants to the target creature are determined only once, at the time the ability triggers. They won’t change if the permanent with backup loses any abilities before the backup ability resolves.
2023-04-14: Each of the tokens copy exactly what was printed on the original creature and nothing else (unless that creature is copying something else or is a token; see below). It doesn’t copy whether that creature is tapped or untapped, whether it has any counters on it or Auras and Equipment attached to it, or any non-copy effects that have changed its power, toughness, types, color, and so on. (Basically, it won’t copy anything that made it modified in the first place. C’est la vie.)
2023-04-14: If the copied creature is a token, the token that’s created copies the original characteristics of that token as stated by the effect that created that token.
2023-04-14: All of the tokens enter the battlefield at the same time.
2023-04-14: If a backup ability causes another creature to gain abilities, the creature with backup will still have those abilities.