The Amulet of Control (5e Equipment)
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Wondrous Item, rare (by a True Neutral character)
"One must be fully able to control one's own body if they wish to face the challenges of life." -Master Chung Wing
This Amulet look like a brown wooden coin on a thin metal chain But when attuned to this item a symbol appears on the coin itself and is any symbol of your choosing(Holy, demonic or otherwise and in any color your want) and the amulet can not be remove from you unless you speak the command word to remove it.
Once fully attuned to this weapon (After a 2 hour mediation, making a wisdom check and at least beating a 15) Your body feels as if it's completely under your control you can now control your body temperature, your breathing, and even the beating of you heart and you can focus on any part of your body to use it's full strength.
You can now add your proficiently bonus to your attacks armed or unarmed, skill checks and saves and in battle you can use a bonus action to speak the command word (word of your choice) and double your proficiently bonus for one round and you now have two bonus actions, but after the round is over you have to take a rest for two rounds and in that time your movement is halved and you cannot make bonus actions and any rolls you make are at disadvantage you can do this twice per day and it reset sets after at next dawn.