In Dragons Race To The Edge why does Dagur call Hiccup brother?

In "Dragons: Race to the Edge," Dagur calls Hiccup "brother" as a sarcastic reference to their complicated relationship and rivalry. Despite being enemies, Dagur acknowledges a sort of twisted kinship due to their shared experiences and backgrounds as dragon riders and leaders. This dynamic adds depth to their interactions, highlighting the tension between their opposing goals while also hinting at a deeper understanding of one another.