.mtgr

Appearance

0029: Companions ​

Status: Accepted. Clarifies decision 0010 (item 3) and decision 0025.

Context ​

Decision 0025 defined putting a companion into hand (special companion), but not the step before it: revealing the companion before the game begins. The companion example introduced Lurrus of the Dream-Den in outside "companion" with no line saying it was revealed, when, or by whom, and keyframes did not list objects outside the game at all. A viewer jumping to turn 4 could not show that a player has a companion waiting, though both players know it for the whole game and play around it.

The label was also a second way to say where the card was. A companion is a sideboard card, and a wish such as Karn, the Great Creator fetching from the sideboard is already written outside "sideboard".

Decision ​

  1. Revealing a companion is a reveal line in the pregame, after the starting player is chosen and before the opening hands are drawn, caused by the card's own companion ability: #1 "Lurrus of the Dream-Den" reveal by #1. The card is introduced with new card just before it. This is the same shape as revealing Chancellor of the Annex (decision 0018).
  2. The starting player's companion is written first, then each other player's in turn order. The rules give no order, so this is a format choice, matching opening hand actions (CR 103.6).
  3. A companion is outside "sideboard". It is a sideboard card, and being a companion is shown by the reveal and the keyframe flag, not by a separate label. Sideboard cards always use the label "sideboard".
  4. Keyframes list a revealed companion while it is still outside the game, with its owner and a companion flag: #1 "Lurrus of the Dream-Den" outside "sideboard" "PlayerA" companion. Other objects outside the game are still not listed.
  5. Once it is put into the game it is an ordinary card and loses the flag. It stays in the game until the game ends (CR 702.139c).

Rules basis ​

Checked against the Comprehensive Rules effective 2026-09-25.

  • 103.2: "Some games require additional steps that are taken after the starting player has been determined." Revealing a companion is one of them, so it follows choose first.
  • 103.2b: "If any players wish to reveal a card with a companion ability that they own from outside the game, they may do so. A player may reveal no more than one card this way ... The revealed card remains outside the game."
  • 103.3, 103.5: the decks are shuffled and the opening hands drawn after those additional steps, so the reveal comes before the opening hand lines.
  • 100.4: a sideboard is "a group of additional cards the player may use to modify their deck between games of a match". A companion is one of these cards.
  • 702.139a: "Before the game begins, you may reveal one card you own from outside the game with a companion ability whose condition is fulfilled by your starting deck."
  • 116.2g: "A player who has chosen a companion may pay {3} to put that card from outside the game into their hand." Revealing the card is choosing it as the companion, which is why the keyframe flag matters for the rest of the game.
  • 702.139c: "Once you take the special action and put the card with companion into your hand, it remains in the game until the game ends."

Alternatives rejected ​

  • A companion pregame statement ("PlayerA" companion #1). Rejected: revealing a card already has a statement, and opening hand reveals use it.
  • An outside "companion" label. Rejected: it gives the same sideboard card two possible labels, and a wish that fetches the companion would have to decide which to use.
  • Leaving companions out of keyframes. Rejected: the companion is public for the whole game and changes how both players play. A keyframe is meant to be the full state a viewer needs (decision 0008).

Consequences ​

  • The spec defines the reveal in the pregame (section 9.1), the "sideboard" label (section 6.7), and the companion keyframe flag (sections 10.3 and 16).
  • The companion example in examples/more-situations.md shows the reveal, the keyframe entry, and the special action.
  • A companion reveal names a card in the opponent's sideboard at the start of the game, which is often enough to classify their archetype (decision 0028).