I need this.

it'll cost you an arm and a leg

But oh, the return on investment...

Turn this into a magic tattoo 

But the things I need to grow back are all my fingers and toes! Ignore the process of me typing this.

What happens if the hand with the ring is chopped off?

It's like a starfish, the ring grows a new body

 I play a warlock (Hexblade).

Is this worth giving up my ring of spell storing?

I always found this item to be odd. I understand that you are regenerating HP and limbs but 1d6 hit points every 10 minutes feels extremely slow when compared to an Oni or a Troll. Its application is really during rests or the entire adventuring day/night. It can essentially replace hit dice during rests but it just doesn't feel impactful in a given combat. Maybe I'm wanting too much, idk.

Quote from TangooseCarmike >>

I always found this item to be odd. I understand that you are regenerating HP and limbs but 1d6 hit points every 10 minutes feels extremely slow when compared to an Oni or a Troll. Its application is really during rests or the entire adventuring day/night. It can essentially replace hit dice during rests but it just doesn't feel impactful in a given combat. Maybe I'm wanting too much, idk.

 It is underwhelming, if it wants to replace hit die it should be of less rarity. I suggest seeing if it would be allowed to heal your con mod min 1 a turn and/or grants max possible when healed.

What happens if you lose the hand that's wearing the ring? Do you grow a new hand and the ring? Or does the hand grow a new you?

you hold the 2 together to re attach.

I have this death knight NPC. My players managed to confuse him so badly that he willingly sat there as they cut off his arm. I think this’ll be useful, since I see nothing against undead using it.

Quote from Mephinyx >>

What happens if you lose the hand that's wearing the ring? Do you grow a new hand and the ring? Or does the hand grow a new you?

 The hand is dead. The ring is on the dead hand. The ring does nothing for the dead hand, as it is dead. The ring can be taken from the hand. If you then put the ring on the other hand or a foot, you can get a new hand.

me too

Could you make a duplicate with this

What is the ruling for broken limbs ?

There was a PC game I played a long time ago that had a scene that stuck with me. While exploring a cave, you come across a human arm sticking out of a bunch of rubble. While you watch it, it twitches slightly from time to time. When you go to touch the arm it falls loose of the rubble, still slightly moving. Once you remove the ring on its hand, it immediately shrivels to dust. And you’re left with a ring of regeneration. 

I always liked that. 

Quote from ClericalKenku >>

But the things I need to grow back are all my fingers and toes! Ignore the process of me typing this.

 I feel like you fell down a hill and now have glue on your hands.

The idea is that you get an extra 6d6 healing over short rests.