Avalanche Caller — ruling 1

A land that becomes a creature because of Avalanche Caller’s activated ability will retain any other supertypes, card types, subtypes, and abilities it had. In particular, it will be a snow creature land.

Avalanche Caller — ruling 2

In most cases, the land that becomes a creature will remain colorless. If another effect caused the land to have one or more colors, the resulting creature land will retain those colors.

Avalanche Caller — ruling 3

The activated ability doesn’t cause the target snow land to become tapped or untapped.

Avalanche Caller — ruling 4

Snow is a supertype, not a card type. It has no rules meaning or function by itself, but spells and abilities may refer to it.

Avalanche Caller — ruling 5

The {S} symbol is a generic mana symbol. It represents a cost that can be paid by one mana that was produced by a snow source. That mana can be any color or colorless.

Avalanche Caller — ruling 6

Snow isn’t a type of mana. If an effect says you may spend mana as though it were any type, you can’t pay for {S} using mana that wasn’t produced by a snow source.

Avalanche Caller — ruling 7

Some cards have additional effects for each {S} spent to cast them. You can cast these spells even if you don’t spend any snow mana to cast them; their additional effects simply won’t do anything.

Avalanche Caller — ruling 8

The Kaldheim set doesn’t have any cards with mana costs that include {S}, but some previous sets do. If an effect says such a spell costs {1} less to cast, that reduction doesn’t apply to any {S} costs. This is also true for activated abilities that include {S} in their activation costs and effects that reduce those costs.

Avalanche Caller : règles, fonctionnement et interactions (MTG)

Avalanche Caller 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

: Target snow land you control becomes a 4/4 Elemental creature with hexproof and haste until end of turn. It's still a land. (A creature with hexproof can't be the target of spells or abilities your opponents control.)

How it works : Avalanche Caller

Original English text — Wizards of the Coast / Scryfall

#1February 5, 2021· Wizards of the Coast
A land that becomes a creature because of Avalanche Caller’s activated ability will retain any other supertypes, card types, subtypes, and abilities it had. In particular, it will be a snow creature land.
No other card is named in this ruling.
#2February 5, 2021· Wizards of the Coast
In most cases, the land that becomes a creature will remain colorless. If another effect caused the land to have one or more colors, the resulting creature land will retain those colors.
No other card is named in this ruling.
#3February 5, 2021· Wizards of the Coast
The activated ability doesn’t cause the target snow land to become tapped or untapped.
No other card is named in this ruling.
#4February 5, 2021· Wizards of the Coast
Snow is a supertype, not a card type. It has no rules meaning or function by itself, but spells and abilities may refer to it.
No other card is named in this ruling.
#5February 5, 2021· Wizards of the Coast
The symbol is a generic mana symbol. It represents a cost that can be paid by one mana that was produced by a snow source. That mana can be any color or colorless.
No other card is named in this ruling.
#6February 5, 2021· Wizards of the Coast
Snow isn’t a type of mana. If an effect says you may spend mana as though it were any type, you can’t pay for using mana that wasn’t produced by a snow source.
No other card is named in this ruling.
#7February 5, 2021· Wizards of the Coast
Some cards have additional effects for each spent to cast them. You can cast these spells even if you don’t spend any snow mana to cast them; their additional effects simply won’t do anything.
No other card is named in this ruling.
#8February 5, 2021· Wizards of the Coast
The Kaldheim set doesn’t have any cards with mana costs that include , but some previous sets do. If an effect says such a spell costs less to cast, that reduction doesn’t apply to any costs. This is also true for activated abilities that include in their activation costs and effects that reduce those costs.
No other card is named in this ruling.