Obtain the Blood of the True Dragon at the Beginning of the End of the World

[Rebirth in the apocalypse + super powers + animal transformation + bloodline + beloved sister + hoarding supplies...] Ling Xuan, who had been struggling in the apocalypse for three years, died together with many people with powers, and was accidentally reborn three hours before the apocalypse began. The two sisters are still alive, and the gentle sister is still there. The apocalypse has not broken out. There is still a chance for everything, and those regrets can be made up for. Just when Ling Xuan was worrying about stocking up supplies but not having any superpower space, the system came to his door and not only gave Ling Xuan the blood of the true dragon, but also gave him a system space as a bonus. Ahem, actually it doesn't matter whether it's bloodline or not, the main thing is to focus on this space... There was no other way. In order to make his sister and sister live a better life in the apocalypse, Ling Xuan could only go on hoarding supplies and hunting high-level zombies and never return... (The protagonist is not the Virgin. He builds a private sanctuary in the early and mid-term, obtains a secret realm in the mid-term, rides Xiaotian and lets himself go completely, and transforms into a dragon in the later stage, either fighting or on the way to fight)