Arkne Gem of luck

A strange gem very hard to find. Just holding it makes you feel Lucky and you randomly decide to test your luck. So you flip a coin it lands heads up you also notice there's a gold coin next to it.

This gem gives you Advantage to most things and gives +10 to your walk speed.

Notes: Bonus: Speed, Advantage: Ability Checks, Advantage: Dexterity Saving Throws, Advantage: Constitution Saving Throws, Feat: Lucky