Fire Emblem Warriors: Three Hopes continues the story of Fire Emblem: Three Houses but seems to be in an alternate timeline to the original, which is fitting of Warriors-style games. It brings back many familiar characters and introduces new ones, such as Arval. This may leave you wondering who Arval is in Fire Emblem Warriors: Three Hopes.
Arval is a mysterious character whoappears in the protagonist’s(Shez’s)dreams and saves themfrom being slain by Byleth, the Ashen Demon. This bears manysimilarities to Sothis, who saved Byleth from dying in Fire Emblem: Three Houses. In theFire Emblem Warriors: Three Hopes - Mysterious Mercenarytrailer, you can hear Arval say, “We are partners in destiny.”

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This strongly implies that Arval will play a similar role to Sothis. Sothis not only saved Byleth, but also gave them an ability called the Divine Pulse that allowed them to rewind time. Fansspeculate that Arval will grant Shez a similar abilityin Fire Emblem Warriors: Three Hopes.
This is further supported by theFire Emblem Warriors: Three Hopesannouncement trailer where you can see Arval’s markings on Shez’s face while fighting Byleth. This is like Byleth’s hair turning light green through Sothis, showing the physical aspects of the mysterious girls who visit them in their dreams.

For more information on Fire Emblem, check outIs there romance in Fire Emblem Warriors: Three Hopes?andAll characters and voice actors in Fire Emblem Warriors: Three Hopeson Pro Game Guides.