Kellan, the Fae-Blooded // Birthright Boon — ruling 1

An adventurer card is a permanent card in every zone except the stack, as well as while on the stack if not cast as an Adventure. Ignore its alternative characteristics in those cases. For example, while it's in your graveyard, Questing Druid is a green creature card whose mana value is 2. It can't be the target of Tenacious Tomeseeker's triggered ability ("return target instant or sorcery card from your graveyard to your hand").

Kellan, the Fae-Blooded // Birthright Boon — ruling 2

When casting a spell as an Adventure, use the alternative characteristics and ignore all of the card's normal characteristics. The spell's color, mana cost, mana value, and so on are determined by only those alternative characteristics. If the spell leaves the stack, it immediately resumes using its normal characteristics.

Kellan, the Fae-Blooded // Birthright Boon — ruling 3

If you cast an adventurer card as an Adventure, use only its alternative characteristics to determine whether it's legal to cast that spell. For example, if you control Johann, Apprentice Sorcerer ("Once each turn, you may cast an instant or sorcery spell from the top of your library.") and Questing Druid is on top of your library, you can cast Seek the Beast, but not Questing Druid.

Kellan, the Fae-Blooded // Birthright Boon — ruling 4

If a spell is cast as an Adventure, its controller exiles it instead of putting it into its owner's graveyard as it resolves. For as long as it remains exiled, that player may cast it as a permanent spell. If an Adventure spell leaves the stack in any way other than resolving (most likely by being countered or by failing to resolve because its targets have all become illegal), that card won't be exiled and the spell's controller won't be able to cast it as a permanent later.

Kellan, the Fae-Blooded // Birthright Boon — ruling 5

If an adventurer card ends up in exile for any other reason than by exiling itself while resolving, it won't give you permission to cast it as a permanent spell.

Kellan, the Fae-Blooded // Birthright Boon — ruling 6

You must still follow any timing restrictions and permissions for the permanent spell you cast from exile. Normally, you'll be able to cast it only during your main phase while the stack is empty.

Kellan, the Fae-Blooded // Birthright Boon — ruling 7

If an effect copies an Adventure spell, that copy is exiled as it resolves. It ceases to exist as a state-based action; it's not possible to cast the copy as a permanent.

Kellan, the Fae-Blooded // Birthright Boon — ruling 8

An effect may refer to a card, spell, or permanent that "has an Adventure." This refers to a card, spell, or permanent that has an adventurer card's set of alternative characteristics, even if they're not being used and even if that card was never cast as an Adventure.

Kellan, the Fae-Blooded // Birthright Boon : règles, fonctionnement et interactions (MTG)

Kellan, the Fae-Blooded // Birthright Boon 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

Double strike Other creatures you control get +1/+0 for each Aura and Equipment attached to Kellan. Search your library for an Aura or Equipment card, reveal it, put it into your hand, then shuffle.

Complete guide

Kellan, the Fae-Blooded is a versatile legendary hero who serves as both a powerful equipment tutor and a battlefield commander. Whether you are searching for the perfect blade or leading a reinforced army, this Human Faerie provides incredible utility through the Adventure mechanic.

Dual Roles: Adventure and Creature

This card exists in two parts. Birthright Boon is a sorcery Adventure that lets you search your library for any Aura or Equipment card. Kellan, the Fae-Blooded is the creature half, featuring double strike and a static ability that buffs your other creatures based on how many Auras and Equipment are attached to him. While in your hand, library, or graveyard, the card is treated only as a creature; however, you may choose to cast the Adventure portion first to tutor for an item before deploying Kellan himself.

The Adventure Path

When you cast Birthright Boon, it goes onto the stack as a White sorcery. As it resolves, you search your library, reveal an Aura or Equipment, and put it into your hand. Instead of going to the graveyard, the card is exiled 'On an Adventure.' From this special exile zone, you may cast Kellan, the Fae-Blooded as a creature later. If the Adventure is countered or fails to resolve, the card goes to the graveyard and you lose the chance to cast the creature from exile.

Scaling Power

Kellan's static ability provides a +1/+0 bonus to all your other creatures for each Aura and Equipment attached to him. Because Kellan has double strike, he is a primary threat on his own, but his presence turns your entire board into a lethal force as you pile on attachments. Note that this bonus only applies to other creatures; Kellan does not give himself the +1/+0 buff from his own ability.

Common Pitfalls

A frequent mistake involves trying to return the Adventure from the graveyard with sorcery-recovery effects. While in the graveyard, this card is strictly a creature card. Another common error is forgetting that Kellan must be cast from exile following the normal timing rules for a creature. You cannot cast the creature half at instant speed unless another effect allows it.

Interaction examples

Tutoring and Deploying

Kellan, the Fae-Blooded // Birthright Boon

Solemn Simulacrum

You cast Birthright Boon for {1}{W}. Upon resolution, you search your library for an Equipment, add it to your hand, and exile Kellan 'On an Adventure.' Next turn, you cast Kellan from exile. If you have Solemn Simulacrum on the battlefield and attach an Equipment to Kellan, the Simulacrum will receive +1/+0 from Kellan's aura-and-equipment-based anthem.

The Throne's Influence

Kellan, the Fae-Blooded // Birthright Boon

Roaming Throne

You have Roaming Throne on the battlefield with 'Human' chosen as the creature type. You cast Kellan, the Fae-Blooded. Note that Kellan's buff is a static ability, not a triggered ability, so Roaming Throne does not double the +1/+0 effect. However, the Roaming Throne itself will receive the +1/+0 bonus for every attachment on Kellan because it is another creature you control.

Double Strike Pressure

Kellan, the Fae-Blooded // Birthright Boon

With no other cards, Kellan is a 2/2 with double strike. If you attach two Equipment cards to him, he remains a 2/2, but any other creatures you control (like tokens) will receive +2/+0. Kellan will deal 2 damage in the first strike step and 2 damage in the regular combat damage step.

Guide written with AI from the official text and rulings. Official English text prevails.

How it works : Kellan, the Fae-Blooded // Birthright Boon

Original English text — Wizards of the Coast / Scryfall

#1September 1, 2023· Wizards of the Coast
An adventurer card is a permanent card in every zone except the stack, as well as while on the stack if not cast as an Adventure. Ignore its alternative characteristics in those cases. For example, while it's in your graveyard, Questing Druid is a green creature card whose mana value is 2. It can't be the target of Tenacious Tomeseeker's triggered ability ("return target instant or sorcery card from your graveyard to your hand").
No other card is named in this ruling.
#2September 1, 2023· Wizards of the Coast
When casting a spell as an Adventure, use the alternative characteristics and ignore all of the card's normal characteristics. The spell's color, mana cost, mana value, and so on are determined by only those alternative characteristics. If the spell leaves the stack, it immediately resumes using its normal characteristics.
No other card is named in this ruling.
#3September 1, 2023· Wizards of the Coast
If you cast an adventurer card as an Adventure, use only its alternative characteristics to determine whether it's legal to cast that spell. For example, if you control Johann, Apprentice Sorcerer ("Once each turn, you may cast an instant or sorcery spell from the top of your library.") and Questing Druid is on top of your library, you can cast Seek the Beast, but not Questing Druid.
No other card is named in this ruling.
#4September 1, 2023· Wizards of the Coast
If a spell is cast as an Adventure, its controller exiles it instead of putting it into its owner's graveyard as it resolves. For as long as it remains exiled, that player may cast it as a permanent spell. If an Adventure spell leaves the stack in any way other than resolving (most likely by being countered or by failing to resolve because its targets have all become illegal), that card won't be exiled and the spell's controller won't be able to cast it as a permanent later.
No other card is named in this ruling.
#5September 1, 2023· Wizards of the Coast
If an adventurer card ends up in exile for any other reason than by exiling itself while resolving, it won't give you permission to cast it as a permanent spell.
No other card is named in this ruling.
#6September 1, 2023· Wizards of the Coast
You must still follow any timing restrictions and permissions for the permanent spell you cast from exile. Normally, you'll be able to cast it only during your main phase while the stack is empty.
No other card is named in this ruling.
#7September 1, 2023· Wizards of the Coast
If an effect copies an Adventure spell, that copy is exiled as it resolves. It ceases to exist as a state-based action; it's not possible to cast the copy as a permanent.
No other card is named in this ruling.
#8September 1, 2023· Wizards of the Coast
An effect may refer to a card, spell, or permanent that "has an Adventure." This refers to a card, spell, or permanent that has an adventurer card's set of alternative characteristics, even if they're not being used and even if that card was never cast as an Adventure.
No other card is named in this ruling.
#9September 1, 2023· Wizards of the Coast
If an effect refers to a card, spell, or permanent that has an Adventure, it won't find an instant or sorcery spell on the stack that's been cast as an Adventure.
No other card is named in this ruling.
#10September 1, 2023· Wizards of the Coast
If an object becomes a copy of an object that has an Adventure, the copy also has an Adventure. If it changes zones, it will either cease to exist (if it's a token) or cease to be a copy (if it's a nontoken permanent), and so you won't be able to cast it as an Adventure.
No other card is named in this ruling.
#11September 1, 2023· Wizards of the Coast
If an effect instructs you to choose a card name, you may choose the alternative Adventure name. Consider only the alternative characteristics to determine whether that is an appropriate name to choose.
No other card is named in this ruling.
#12September 1, 2023· Wizards of the Coast
Casting a card as an Adventure isn't casting it for an alternative cost. Effects that allow you to cast a spell for an alternative cost or without paying its mana cost may allow you to apply those to the Adventure.
No other card is named in this ruling.