Freyr and Frejya
Freyr (フレイ Furei) is a mysterious boy who summons the Evolved Heart Roidmude, the Terror Dopant, the Lord Baron, the Sagittarius Nova, the Kyouryu Greeed, and the original White Wizard. He also steals all of the heroic Eyecons from Ghost and Specter, as well as the former's Toucon Boost Eyecon, rendering both of them powerless without their form changes.
Freyja (フレイヤ Fureiya) is a mysterious girl who tells Takeru and Makoto to collect the Legend Rider Eyecons and use them to stop Freyr from his plans on destroying the current Kamen Riders after Freyr steals their heroic Eyecons.
They soon returned during Adel's last schemes, as well as revealed that they are one person, with Freyja is the main body and both are a messenger to the Great Eye, as the entity itself is interest in Takeru, due to his heroic deed as the humanity's last hope. The twins warned Takeru of the newer threat who is much worse than Adel's will approach soon enough, which turns out to be none other than the Gammisers themselves, who had been manipulating Adel all along, including the creation of Makoto's doppelgänger to backup their minds into the clone's Deep Specter Eyecon to enact their plan on destroying humanity. Unfortunately for Takeru and his allies, they are too late to prevent the Gammisers' backup plan, as they completely possesses the Great Eye and using Freyja's body as the new vessel, evolving into the Great Eyeser. However, thanks to Ryū Tenkūji's spirit, Ghost manages to kill the Great Eyeser, freeing the Great Eye and Freyja.
Freyr and Freyja are both portrayed by Ryo Ogawa (小川 涼 Ogawa Ryō).