Kellan, the Kid — ruling 1

If the spell you cast that caused Kellan, the Kid’s last ability to trigger has {X} in its mana cost, X is the value chosen as that spell was cast for the purpose of determining its mana value.

Kellan, the Kid — ruling 2

If the spell you cast that caused Kellan, the Kid’s last ability to trigger is represented by a split card, the characteristics of the half you didn’t cast are ignored while that spell is on the stack. For example, if you cast the Cease half of Cease // Desist from the Murders at Karlov Manor release, that spell’s mana value is 2 because Cease’s mana cost is {1}{B}{G}.

Kellan, the Kid — ruling 3

A permanent spell is an artifact, battle, creature, enchantment, or planeswalker spell.

Kellan, the Kid — ruling 4

If you cast a spell “without paying its mana cost,” you can’t choose to cast it for any alternative costs. You can, however, pay additional costs, such as kicker costs. If the spell has any mandatory additional costs, those must be paid to cast the spell.

Kellan, the Kid — ruling 5

If the permanent spell you cast has {X} in its mana cost, you must choose 0 as the value of X when casting it without paying its mana cost.

Kellan, the Kid — ruling 6

Putting a land card onto the battlefield with Kellan’s last ability doesn’t count as playing a land. It can put a land card onto the battlefield even if you’ve already played your land for the turn.

Kellan, the Kid : règles, fonctionnement et interactions (MTG)

Kellan, the Kid 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

Flying, lifelink Whenever you cast a spell from anywhere other than your hand, you may cast a permanent spell with equal or lesser mana value from your hand without paying its mana cost. If you don't, you may put a land card from your hand onto the battlefield.

How it works : Kellan, the Kid

Original English text — Wizards of the Coast / Scryfall

#1April 12, 2024· Wizards of the Coast
If the spell you cast that caused Kellan, the Kid’s last ability to trigger has in its mana cost, X is the value chosen as that spell was cast for the purpose of determining its mana value.
No other card is named in this ruling.
#2April 12, 2024· Wizards of the Coast
If the spell you cast that caused Kellan, the Kid’s last ability to trigger is represented by a split card, the characteristics of the half you didn’t cast are ignored while that spell is on the stack. For example, if you cast the Cease half of Cease // Desist from the Murders at Karlov Manor release, that spell’s mana value is 2 because Cease’s mana cost is .
No other card is named in this ruling.
#3April 12, 2024· Wizards of the Coast
A permanent spell is an artifact, battle, creature, enchantment, or planeswalker spell.
No other card is named in this ruling.
#4April 12, 2024· Wizards of the Coast
If you cast a spell “without paying its mana cost,” you can’t choose to cast it for any alternative costs. You can, however, pay additional costs, such as kicker costs. If the spell has any mandatory additional costs, those must be paid to cast the spell.
No other card is named in this ruling.
#5April 12, 2024· Wizards of the Coast
If the permanent spell you cast has in its mana cost, you must choose 0 as the value of X when casting it without paying its mana cost.
No other card is named in this ruling.
#6April 12, 2024· Wizards of the Coast
Putting a land card onto the battlefield with Kellan’s last ability doesn’t count as playing a land. It can put a land card onto the battlefield even if you’ve already played your land for the turn.
No other card is named in this ruling.