Best-of-one
Best-of-one, often shortened to Bo1, is a match structure in Magic: The Gathering consisting of only a single game. This is in contrast to the best-of-three (Bo3) match structure, where the first player to win two games wins the match and both players have an opportunity to sideboard between each game.
Although any instance of playing just a single game of Magic could technically be described as "best-of-one", the term is most frequently used in reference to games played on Magic: The Gathering Arena, where it is a popular match structure even for competitive constructed formats (such as Standard and Pioneer) that would traditionally use a best-of-three structure.
In the context of limited play Arena often refers to Bo1 as "premier" (e.g. "Premier Draft"), although this is occasionally dropped altogether with the assumption of Bo1 being the default (e.g. an event simply titled "Sealed" is likely Bo1). In contrast, Bo3 limited events are referred to as "traditional" (e.g. "Traditional Draft", "Traditional Sealed"). Wizards of the Coast used to refer to Bo1 Standard on Arena by the name Arena Standard, although this terminology is not regularly used anymore.[1][2][3]
Description
In addition to the number of games played being different, there are several additional differences that Bo1 play on Arena has from Bo3 play.
- Some formats have additional bans that apply only to the Bo1 queues on Arena.
- Starting hands are randomized in a way that should reduce the frequency of mulligans, but without incentivizing mana base construction outside the strategic norms of the game. Wizards feel this achieves the desired effect of reducing the frequency of mulligans without changing how players build their mana bases. The only concrete statement regarding the shuffler was released during closed beta play, and in the updates since it has been unclear whether the algorithm has changed.
- The system during the beta drew an opening hand from each of two separately randomized copies of the decks and leaned towards giving the player the hand with the mix of spells and lands (without regard for color) closest to the average for that deck. This formula usually yielded three lands in one's starting hand because 22÷60×7≈2.567 and 30÷60×7=3.5.
- You can then use the London Mulligan rules to get a new hand with one fewer card. Mulliganed hands are created from a single randomized draw.
- Although matches consist of only one game, the sideboard can still be used for cards with spells and abilities referencing "outside the game", such as Companions or Mastermind's Acquisition. As of April 15, 2021, best-of-one sideboards are restricted to a maximum of seven cards.
- In the past, there were several cards not printed in any (Bo3) Standard-legal sets (and therefore are not legal to play in Bo3 Standard), yet were still legal to play in Bo1 Standard. These cards were released as part of the Arena-exclusive Arena Base Set, and copies of these cards were included in one of the various starter decks which were made available to all new Arena players. These cards are no longer legal in Bo1 Standard (nor Bo3 Standard).
Bo1-specific bans
- See also: Banned and restricted cards/Timeline
By default, the Bo1 and Bo3 queues of a format use the same banned and restricted list. However, due to the lack of sideboarding in Bo1 play, some cards and strategies that are of an acceptable power level in Bo3 play become too powerful when the ability to sideboard is lost in Bo1. Thus, there have occasionally been Arena-specific bans that apply only to the Bo1 queues. Cards that currently have Bo1-specific bans in one or more formats on Arena are listed below.
- Standard: Leyline of Resonance was banned in Bo1 in October 2024 for enabling turn two wins without an opponent being able to respond in any practical manner.[4]
- Pioneer: Tibalt's Trickery was banned in Bo1 on June 30, 2025 due to its ability to cast expensive spells in the very early game by countering one's own spells.[5]
Previously-banned cards
The following is a list of cards that have received a Bo1-specific ban at some point in the past.
- Nexus of Fate was banned in Bo1 Standard in February 2019 due to the ease with which it could be recurred for infinite extra turns.[6]
- The Book of Exalted Deeds was banned in the the preview-queue Standard 2022 format.[7]
References
- ↑ Ryan Spain (December 1, 2017). "Best-of-One Starting Hand and Mulligan Rules". Forum post. MTG Arena Forums. Archived from the original on September 17, 2021.
- ↑ Chris Clay (May 25, 2018). "State of the Beta for May 25th, 2018". Forum post. MTG Arena Forums. Archived from the original on September 22, 2021.
- ↑ Paulo Vitor Damo da Rosa (January 20, 2019). "Best-of-One vs. Best-of-Three". ChannelFireball. Archived from the original on Septmeber 24, 2021.
- ↑ Wizards of the Coast (October 22, 2024). "MTG Arena Banned and Restricted Announcement - October 22, 2024". magicthegathering.com. Wizards of the Coast.
- ↑ Carmen Klomparens, Jadine Klomparens, Arya Karamchandani, Gavin Verhey & Dave Finseth (June 30, 2025). "Banned and Restricted Announcement – June 30, 2025". magicthegathering.com. Wizards of the Coast.
- ↑ Wizards of the Coast (February 14, 2019). "MTG Arena Banned and Restricted Announcement". magicthegathering.com. Wizards of the Coast. Archived from the original on 2019-02-14.
- ↑ Wizards of the Coast (July 14, 2021). "MTG Arena Announcements, July 14, 2021". magicthegathering.com. Wizards of the Coast. Archived from the original on 2021-07-14.