This Weavile is my competitive maison farmer, and leveled up from a Sneasel knowing Ice Shard. Later on, I overwrote the move to use him for breeding, and now he apparently can't relearn it. What happened?
Move Reminders are restricted to teaching a Pokémon only moves that its species can learn; they cannot teach moves exclusive to an earlier evolution.
Because Ice Shard can only be learned by level up as a Sneasel, it cannot relearn it as a Weavile.
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