• Not genre-limiting
  • "But what about genres that don't usually have HP bars?" It encourages innovating on those genres to see how they might work with an HP bar
  • For example, racing games could easily have HP bars implemented, vehicular combat is an existing genre & Mario Kart already has bombs, banana peels, etc. that could do damage to an HP bar. Now you just have to get that HP bar to pull double-duty. Maybe your current health level is also the maximum speed of your racecar, now you have another incentive to stay alive and to get health boost items.
  • Health bar functioning as a timer in a puzzle game. Clear your Match 3s or Tetris lines to get more time. Bad moves hurt you. Certain Match 3 shapes or number of Tetris lines cleared gives you more hp or something. Now you've got a puzzle game with both health and a timer.
  • Honestly, just getting an HP bar to mesh with a visual novel would probably end up with it pulling some kind of double duty anyway. Like HP level influencing your story branch or changing what choices you're able to make.
• Doesn't tell you what your mechanic is, only that a common gameplay element is pulling double-duty
• Doesn't imply any kind of setting, unlike Harvest, where almost every game was somehow set on a farm even when it wasn't a farming game
• Actually inspires mechanical ideas, which is the important part of brainstorming so you can start prototyping as soon as the jam starts

this has been my proper gander at the HP bar theme