Oui, exacte. Voici les références de règles.
107.4h The snow mana symbol {S} represents one mana in a cost. This mana can be paid with one mana of any type produced by a snow permanent (see rule 205.4g). Effects that reduce the amount of generic mana you pay don’t affect {S} costs. Snow is neither a color nor a type of mana.
205.4g Any permanent with the supertype “snow” is a snow permanent. Any permanent that doesn’t have this supertype is a nonsnow permanent, regardless of its name.
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"Just a reminder that when it comes to a land, the correct choice is always John Avon."
- Anonymous hero