• As one of the Undead, you are immune to poison and disease.
• You do not need to eat, drink or breath.
• You don’t need to sleep, and magic can’t put you to sleep.
• Skeletons can be of any age. An Animated skeleton cannot be affected by age deterioration and are immune to magical ageing effects.
• When you take a long rest, you must spend at least four hours in an inactive, motionless state, rather than sleeping. In this state, you can appear to be a pile of bones, but it doesn’t render you unconscious, and you can see and hear as normal.
• As one of the undead and you are damaged by Cleric, Druid and Paladin based healing spells. 

You have already died once, you have advantage on death saving throws.