|Land-Air Single Combat|
|Season 2, Episode 10|
|Air date||September 8, 2012|
|Episode Director||Masato Jinbo|
|Animation Director||Akinori Fudesaka, Kayo Nomichi, Shunryō Yamamura|
|Ending||Natsu no Yakusoku|
DD2 Episode 9
DD2 Episode 11
Land-Air Single Combat (空陸一騎打ち！ Sora-Oka Ikkiuchi!) is the tenth episode of the second season of the Dog Days series. It first aired on September 8, 2012.
The Union Festival keeps going at full force with several one-on-one battles among key players of the three nations. Nanami challenges Brioche, while Shinku and Gaul have a duel using their Hero Crystals and Milhi has a heated aerial match with Rebecca. Seeing her country behind in the overall score, Adel decides to join the fight adopting the "secret" identity of Hero Mask.