when you unequip an item, if this one has + XX HPs then when you will unequip it you will loose hps.
example
you have 100/100 hps
you equip +100 item
you are at 100/200 hps now
if you unequip your item without heal you will be at 0/100 so that kill you
just make sure you are healed before put off any + xx hps
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