After saying farewell to X, , and , Zero gave Rui a love hand symbol and a smile flash while quickly saying hello and goodbye before he left with the other Cyber Card Ultras.
That's seriously the plot and it's awesome! In a last effort, Zero and Mirror Knight tried to shield Planet Esmeralda from Belial's Arch Deathcium Beam and ultimately lost his life from exhaustion.
However, he was kept within his and fell alongside other Spark Dolls to Earth.