Kyusei Sentai Wakuseiber Special Episode 3

Following the tragic loss of the original Yellow Sun, the giant monster Minotaros begins to rampage through the city while the remaining four Wakuseiber struggle to pilot their combined mecha. However, the fallen ranger's younger sister, Hana, bravely steps up to take his place as the second-generation Yellow Sun. With their team complete once again, they successfully unleash their ultimate attack to destroy the monster, though Hana collapses from exhaustion immediately after the battle. (Source: MyDramaList)