Well, what can I say, a simple top-down movement game with some intense fight as the longer the player survives, which does meet the theme in some way.
But the different thing is, you exchange your HP "indefinitely" every time you gain EXP by killing enemies or your HP value drops when being hurt by the enemies. Levelling up can gain you some stats bonus when gaining EXP.
And you can die by just killing enemies and without getting hurt as you gain EXP infinitely... Just don't know why I'm liking this!