Snow and fire counteract each other. If Song Jian were to only use a long sword to execute Snowy Dusk, the sword qi of snowflakes appearing for an instant would be immediately reduced to nothing by the fire of the Fire Elemental Lord.
However, using four long swords simultaneously to employ Snowy Dusk puts the Fire Elemental Lord at an immediate disadvantage;
The surface flames are extinguished by the snowy sword qi, but an endless amount of fire elemental power still resides within the Fire Elemental Lord;
The more suppressed it gets, the more fiercely the continuing fire elemental energy within its body responds. With the snow and ice piling on, Song Jian's remaining Spirit Points are already insufficient to deploy four sets of Snowy Dusk simultaneously;