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I've been assuming since I started DM-ing a D&D 5e campaign that a PC can sleep in light armor, but not medium or heavy armor without gaining levels of fatigue. However, I am now playing a Fighter in a different campaign and I'm not seeing those rules anywhere. Does 5th ed. allow PCs to sleep in medium or heavy armor with no penalty? I'm thinking at this point that my memory of 3.5e flavored the rules that I was DM-ing by.