|“||Rex can hit multiple opponents with a huge pillar of fire, launching them away. This Final Smash deals less damage than Mythra's, but it has higher launch power and can more easily KO opponents.||”|
|—Description from Ultimate's Move List.|
Burning Sword is Pyra's Final Smash.
Once activated, Rex will be summoned and performs a wide overhead slash of the Aegis. If any fighters are caught, it will then transition to a brief cutscene where Pyra and Rex will hold the Aegis together and leap towards the opponents while shouting the move's name. It then cuts back to normal gameplay view, where the two perform a wide upwards slash at the opponents with the Aegis, now on fire, which then creates a large pillar of flame that hits multiple times (similar to Entei's Fire Spin). It then ends in an explosion, with Pyra exclaiming "Witness our power!" and Rex disappearing.
In comparison to Mythra's Final Smash, Sacred Arrow, it is much stronger with a focus on KO'ing opponents instantly. Much like Sacred Arrow, the move can only trap up to three opponents; however, the large pillar of flame can attack any other nearby characters and potentially KO them as well.
Burning Sword is Pyra's Level IV Blade Special in Xenoblade Chronicles 2; the in-game description describes the move as "Cleave the enemy with a giant sword of flame that detonates on impact". In the game, it is Pyra's signature move, and even performs it at times with Rex during certain cutscenes. Its depiction in Smash is a near exact recreation of the original save for the trapping slash at the beginning, which is an original addition.
|Pyra's Special Moves|
|Standard Special||Flame Nova|
|Side Special||Blazing End|
|Up Special||Prominence Revolt|
|Down Special||Swap to Mythra|
|Final Smash||Burning Sword|