Gunpla Builders Beginning G Blu-ray contains episodes 1-3 of the OVA directed by Kou Matsuo.

An anime created to commemorate the 30th anniversary of Gundam plastic models, with "Gunpla" as its main theme. The young Haru Irei has a fateful encounter with an extremely rare Gunpla, the Beginning Gundam. After building this Beginning Gundam, Haru learns about and participates in the Gunpla Battle game. As he meets Kouji and other powerful rivals, Haru grows up...