Quick answer: In the Graveyard Keeper 2 energy system, the blue bar is Energy (max 100). Almost every manual job (chopping, digging, crafting, autopsies, studying) spends it, and food, drink and sleep refill it. The purple part creeping in from the right is insanity: each point removes one point of maximum energy, so your energy can't go above 100 minus insanity. The gold thumbs-up number next to it isn't health; it's your Town Gratitude.

French players search nouveau système d'énergie ("new energy system"); this page is the answer. Players who search health bar are usually looking at this same bar: the bar at the top is energy, and health comes into play in battles, where fights use stamina instead of energy. What is the ok icon under the energy bar is the thumbs-up, which is Town Gratitude.

Quick facts

  • Blue bar: Energy, max 100
  • Purple part: insanity; each point costs 1 max energy
  • Insanity cap: 80, which leaves only 20 energy
  • Thumbs-up number: Town Gratitude, not health
  • Combat: uses stamina, not energy

What refills energy

SourceEnergy
Sleeping in your bedfull
Elder's meal+120
Fisherman's pie, Burger+80
Fried golden carp, Grape Juice (gold)+60
Tavern beer+52
Berry pie+30

Bread is the easy early staple: in a recorded 100% playthrough the player queued 80+ loaves in the oven to keep working. Some food raises insanity, though: Burger +5, Baked meat +10, Soldier's ale +20.

How to clear the purple bar

Item / actionInsanity
Wine (gold / silver / bronze)−35 / −30 / −25
Chocolate−20
Sleeping off Lack of Sleep−20
Tavern beer−12
Berry pie−3
Writing stories at the deskuses insanity up

A normal night's sleep does not lower insanity. Sleep removes 20 only when you're sleeping off the Lack of Sleep debuff. In a recorded 100% playthrough: "if I didn't have the tired debuff, my sleeping didn't remove insanity."

The Lack of Sleep debuff

Stay up about two days

You get Lack of Sleep.

Every point of energy now adds insanity

Half a point of insanity per point of energy spent, which is "the purple bar encroaching on my energy bar".

Sleep it off

Once your energy is full again you lose 20 insanity. The game saves when you sleep (How saving works).

The Iron Will perk lowers the insanity ceiling to 70, so you always keep at least 30 energy.

FAQ

Related

Sources: a recorded 100% playthrough and a 7-tips guide on YouTube, wikily.gg, Fextralife.