Sky X Heart last survival is a love letter to the Baldr series, it was also the second to last from the franchise. It really is nothing more but the gameplay of Baldr Heart in 2 different survival modes. one normal where you can just jump in every 5 stages to a seemingly infinite stages. The second on is hell survival where you can't restart you will always start from the beginning if you die or quit.
The moveset is 100% baldr heart but some bosses and elite enemies from Sky dive 1, dive 2 and dive X made it in. You can unlock fanarts and every piece of music from the entire franchise.
This game was only available inside the masterpiece chronicle collection box as a disk.
It's sad that Giga shutdown and you can't get the game anymore. But funnily enough the servers/leaderboad is still up and functioning with some people having insane scores even on hell mode.