The Heritors of Arcadia (アルカディアの継ぎびと Arukadia no Tsugi Bito, lit. Arcadia's Successors in the Japanese version) is the Ending Credits song of Fire Emblem Echoes: Shadows of Valentia. It is sung by Janis Crunch in the Japanese version and by Bonnie Gordon, voice actress of Silque, in the English version.
The English version appears to be a song from Mila's perspective at the end of Echoes recounting the events of the story. It references a Jasper Lion who will lead the people into a promised land and a better future. The song alludes that, despite Mila's death, she will still be watching over the humans and be there to protect them in their time of need - likely referencing the importance of the Mila Tree as a location in Fire Emblem Awakening.
In an interview with Bonnie Gordon, she was not planned originally to be the singer. She auditioned when she overheard the Sound Engineer and Director mentioning that they were looking for someone to perform the song.
The octave change between the Japanese and English versions is due to Bonnie Gordon's slightly lower vocal range.
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