HALO FOILCheapest priced copy (Ikoria: Lair of Behemoths): $0.99 at Card Kingdom, near mint, their price list as of .
Gyruda, Doom of Depths 
Legendary Creature — Demon Kraken · 6/6 · Rare · Multiverse Legends · #172
Companion — Your starting deck contains only cards with even mana values. (If this card is your chosen companion, you may put it into your hand from outside the game for {3} as a sorcery.)
When Gyruda enters, each player mills four cards. Put a creature card with an even mana value from among the milled cards onto the battlefield under your control.
Legal inCommanderPioneerModernLegacyVintage
Not legal inBrawlStandardPauper
9 printings · $0.99 to $12.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Ikoria: Lair of Behemoths | 221 | Rare | $0.99 | $1.49 |
| Ikoria: Lair of Behemoths | 351 | Rare | $1.79 | $2.99 |
| Ikoria: Lair of Behemoths (Gigan, Cyberclaw Terror) | 384 | Rare | $9.99 | $10.99 |
| Multiverse Legends | 42 | Rare | $0.99 | $1.99 |
| Multiverse Legends | 107 | Rare | — | — |
| Multiverse Legends | 172 | Rare | — | $12.99 |
| Multiverse Legends | 172z | Rare | — | — |
| Ikoria: Lair of Behemoths Promos | 221p | Rare | $1.49 | $3.49 |
| Ikoria: Lair of Behemoths Promos | 221s | Rare | — | $1.49 |
16 rulings from Wizards of the Coast
- 17 April 2020If a replacement effect causes a player to exile the top four cards of their library instead of putting them into their graveyard as Gyruda's triggered ability resolves, the creature card you choose may be one of those cards in exile.
- 17 April 2020If you reveal a companion outside the game, for as long as it remains there, you may pay {3} any time you could cast a sorcery (that is, you have priority during your main phase and the stack is empty). Once you do, you put it into your hand and behaves like any other card you've brought into the game. For example, if it's discard, countered, or destroyed, it's put into your graveyard, remaining in the game. This is a change from previous rules.
- 17 April 2020If more than one player wishes to reveal a companion, the starting player does so first, and players proceed in turn order. Once a player has chosen not to reveal a companion, that player can't change their mind.
- 17 April 2020The companion's other abilities apply only if the creature is on the battlefield. They have no effect while the companion is outside the game.
- 17 April 2020You may have one companion in the Commander variant. Your deck, including your commander, must meet its companion requirement. Your companion is not one of your one hundred cards.
- 17 April 2020The companion ability has no effect if the card is in your starting deck and creates no restriction on putting a card with a companion ability into your starting deck. For example, Zirda may be in your starting deck even if your other permanent cards don't all have activated abilities.
- 17 April 2020Paying {3} to put your companion into your hand is a special action. It doesn't use the stack and players can't respond to it. Once you take this action, you may cast that card if it's legal to do so before any other player can take actions.
- 17 April 2020Your companion begins the game outside the game. In tournament play, this means your sideboard. In casual play, it's simply a card you own that's not in your starting deck.
- 17 April 2020If a card in a player's graveyard has {X} in its mana cost, X is considered to be 0.
- 17 April 2020The requirements of the companion ability apply only to your starting deck. They do not apply to your sideboard.
- 17 April 2020Before shuffling your deck to become your library, you may reveal one card from outside the game to be your companion if your starting deck meets the requirements of the companion ability. You can't reveal more than one. It remains revealed outside the game as the game begins.
- 17 April 2020A card with mana value 0 has an even mana value.
- 1 June 2020Wizards of the Coast has issued functional errata for the Companion mechanic. Instead of casting companions from outside the game: Once per game, any time you could cast a sorcery (during your main phase when the stack is empty), you can pay {3} to put your companion from your sideboard into your hand. This is a special action, not an activated ability. It happens immediately and can’t be responded to. It can’t be countered or stopped by cards like Phyrexian Revoker. For more information please see https://magic.wizards.com/en/articles/archive/news/june-1-2020-banned-and-restricted-announcement
- 1 June 2020Paying {3} to put your companion into your hand is a special action. It doesn't use the stack and players can't respond to it. Once you take this action, you may cast that card if it's legal to do so before any other player can take actions.
- 1 June 2020If you reveal a companion outside the game, for as long as it remains there, you may pay {3} any time you could cast a sorcery (that is, you have priority during your main phase and the stack is empty). Once you do, you put it into your hand and behaves like any other card you've brought into the game. For example, if it's discarded, countered, or destroyed, it's put into your graveyard, remaining in the game. This is a change from previous rules.
- 1 June 2020Once you put your companion into your hand, it behaves like any other card you’ve brought into the game. For example, if it’s countered or destroyed, it’s put into your graveyard, remaining in the game.