Do I die immediately if I hit 0% energy? Or can I continue slaving away in this iron mine that is far too hard for the rest of my villagers?
W3 to W6 - Blockland. Special mentions: New Avalon, Tarn of Hotdog, Red October. W7 - Elvenia, til we all got lazy. W8 - Cult of R'lyeh, til the deeps called us back. W9 - Tartarus, til death/wizards came for the land itself. W10 - ???, ruined and forgotten.
I got down to 300-200% drinking water to light a fire and it gave me 80-90 somthing starvation damage, so my assumption is yes 0% will mean death, it took 2-3 days of playing all day stuffed to heal
You take starvation damage when your energy drops to 1000% or less. To heal it you have to be at 4000% or more and stay there. That said, never, never, never, NEVER let your energy get that low. I've only take 2 points of starvation damage at a time simply for being at <1000 so I don't know where 80-90 comes from. Most damage I've had is 6.