Cloak of Dragon Power (5e Equipment)
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Wondrous item (cloak), very rare (To attune to the cloak of dragon power you must speak Draconic and have slain one or more dragons older than wyrmling or you must spend 1 month discovering the cloaks secrets)
A cloak that allows the wearer shift into a half-draconic form granting (based on the corresponding dragon type), the horns, claws, and wings of a dragon for an hour once every week.
When you use the cloaks power to shift into your half-draconic form you get +2 to your Armor Class, your Strength, Dexterity, and Charisma scores change to 21 (you are unaffected by this if you have an ability score higher than this) and you are given temporary hit points equal to half of your max HP(rounded down). These bonuses are not applied when you are not in half-draconic form.
If the wearer has been attuned to the cloak of dragon power for a year you gain the breath weapon of the dragon of your choice. The breath attack does 8d6 (dragon's type) damage (the target must make Dexterity saving throw with a DC of 14). You can use the breath attack up to 1 time a day. At 2 years you gain a second use. At 5 years you gain a third and at 10 years you gain a 4th. You regain all uses of this breath weapon after you finish a long rest.
If the wearer has been attuned to the cloak for 50 or more years you can summon one young dragon that is tame to you (that corresponds with the breath weapon you chose), this dragon can only be summoned once and if it dies, you can not summon another one. You can also change into your half draconic form permanently, granting you some of the life of a full dragons (around 3-6 centuries).