Question: Who competed in the battle of Xerxes?
Paraphrase: Who competed within the fight of Xerxes?
SPARQL (Wikidata): SELECT ?answer WHERE { wd:Q18217408 wdt:P607 ?X . ?X wdt:P710 ?answer}
Answer: Byzantine Empire, Kingdom of Iberia, Huns, Sasanian Empire, Kingdom of Aksum, Belisarius, Heruli, Sabir people, Sittas, Ghassanids, Lakhmids