In Ultra Age, you will quickly take damage if you are not aware of all the enemies you are up against. In the first tutorial area, while Helvis is hovering around you, you cannot heal at all. Any damage you take, you will have to live with that short amount of health until the boss fight.
After the boss fight, you will learn how to heal. You will encounter massive Blue Crystals on your travels, and you can absorb these with the relic you have acquired and turn them into Energy. Interact with a Blue Crystal and hold down the A or X button, and the energy will be absorbed.
Once you have this Energy, all you need to do is press down on the D-Pad, and you will get some health back. In the bottom left corner of the screen, you will see the d-pad menu. When you have energy, the down d-pad icon will start to fill up white.
When used, the white will begin to drain. This is how you can keep on track of how much energy you have left for healing. When there is no white left, there is no more energy, so you cannot heal. You need to find another blue crystal to absorb energy to heal once again.
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