The "Legendary Hero of the Azure Planet", Riser Shirogane is the physical manifestation of JustiPower sealed away within the Justi Crystal that Nolun gave to the Tendo Clan centuries ago. However, by combining the hearts of the three Justirisers, and the prayers of the Justi Crystal bearer, Glen becomes the vessel through which Shirogane comes into being. Becoming Shirogane grants Glen immense power that can easily defeat even the strongest enemy. It also changes Shouta's personality to a calmer and non-violent kind, contrasting the original to such an extent that he has on many occasions even spared an enemy or gave them a chance to retreat, only to be forced to kill them when they refuse. Becoming Shirogane caused shock to Shouta's body the first few times, but afterwards he was able to transform without difficulty. However becoming Shirogane takes an even larger toll on Mio, and she is usually unconscious for some time after a battle in which he is summoned.
Shirogane can summon forth the multi-mode weapon "JustiArms" in combat. This powerful weapon has three modes that is reflective of the three Justirisers' Specialties: "JustiBlade" resembling Riser Glen's close-combat specialty; "JustiBlaster" resembling Rider Gant's ranged combat specialty; and "JustiLancer" resembling Riser Kageri's speed combat specialty. Its core power has the combined powers of all 3 Justirisers magnified by the JustiCrystal that Mio holds and lasts as long as she can maintain the unity within it. Its powerful finisher "JustiCrash" is also a resemblance of Riser Glen's "Raging Flame" finisher but with the combined powers of the three Justirisers' energy that is capable of taking out the most powerful of enemies.
In the final battle, the fusion of Mio's Justi Crystal and Rigel's Riser Power gave birth to a new "Mirage Power" that allowed the three Justirisers as well as their GenSeiJuu to fuse into one single entity in the form of a "Giant Riser Shirogane" to take on the Giant Kurogane Beast. This form and finisher is exactly the same one as the human-sized version, but scaled-up in magnitude and power as well as gaining the power to deflect attacks similar to that of Shirogane's GenSeiShin "Ryuuto".