Suggest improvements to the Health Bar issue.

Play Trials of Fire. However, when you reach the 2nd last level, you will find that if you hit the boss only once, his health bar will drop to 0 and he will disappear. Anyone can help on that?
Here is the link to Trials of Fire.
http://www.flowlab.io/game/play/648867

Have a once set the boss’s bar to the starting health, that way, when the level restarts, he stays alive after a hit

Thanks, @jngthree! It helped.