How do you up your Health Bar?

You can't. Sorry dude.Unless you mean by getting the cyber elf and turning it big other than the tiny thing.

There is a way but you must have a fully upgraded cyber elf but you also have to have all 4 sub tanks one from the hibernation chamber wich is easy because you need to use you're z knuckle to grab the chip from dat wierd thing from the hibernation chamber wich has a chip over himself and another sub tank is from dat place with dat wierd plant boss person girl but the sub tank is in the whole place just find it somewhere srry I forgot where it is the last two you get from this guy in the last door from the giant truck wich you need to make 2 s-crystals wich you use these following chips Faital Mechameson V.Fire and Ceratanium and go to the hibernation chamber and use your level 5 hacker cyber elf and fight dat thing dat shoots a lot of serpent gears and fight it but don't destroy the hatches and when you filled up the 4 sub tanks escape and use your level 7 nurse elf and escape when you get in and dats it