I'm in Minecraft single player and would like to set that you can heal up quickly without potions, is that possible? (Version 1.8.9.)
On peaceful or use a mod
You could give yourself the rain lotion effect for a long time. Otherwise this is not possible without mods
Peaceful
Yes, or eat so you don't have to go hungry. You can't do anything else unless you hack or cheat
I can give myself regeneration for a long time but that disappears after rejoining
Can it be yes maybe I'm command blocks when joining
You write in a command block:
/ effect Name regeneration 1 255 true
And you build a clock on this command block
Goes 100%