On Theros, an oracle promised Niko an undefeated athletic career. They broke that future by missing on purpose, survived the force sent to restore fate and sparked into the Multiverse. Kaldheim gives the newly free Planeswalker anonymity, practical work among the Kannah and an unfamiliar culture in which reputations are earned through deeds retold by others.
Fynn's vision warns that Koma will reach Starnheim, but clan rivalries turn the warning into an argument over whose testimony deserves belief. Birgi, hidden among the mortals, lets that tension erupt into a brawl. Niko refuses both the provocation and the Valkyries' expectation that somebody must die before order can return.
To stop a death, Niko traps the reaper Avtyr inside a mirror shard. The act violates Kaldheim's spiritual order but proves that the supposedly fixed rules can bend. Rather than flee the consequences, Niko accepts Orhaft's dangerous route through an Omenpath and carries the warning toward Starnheim personally.