Every second day of Easter in Kastanoussa, Serres, a custom is revived with deep roots in Pontus. The Egg Battles, brought by refugees from Pontus when they settled in the area, continue with great enthusiasm in the village. The custom began among groups of friends competing to see whose egg was the strongest, and since 1926, when the village took the name Kastanoussa, it has continued and developed into its competitive form thanks to the support of the Cultural Association of Kastanoussa.

In their modern version, the Egg Battles are held under strict rules. Each participant brings 30 boiled white eggs, and after the Divine Liturgy, the contestants take their places on two large platforms in the school courtyard. The contest begins with the challenge of who will manage to break the most eggs. The goal is for the strongest egg to survive and prevail at the end of this exciting competition. The Egg Battles continue to strengthen local tradition and bring the community closer together every year, creating a sense of unity and celebration.