Hendecagon

Wondrous item, uncommon (requires attunement)

This eleven-sided ring is a holy symbol from an ancient and long extinct religion. Every 11th day at dawn after you have attuned to this item, one of the following effects occurs. Unless otherwise stated, all effects disappear at the end of your next long rest.

2d6	Effect
2	You suffer a vision of the Eleven Profane Tides and your energy is sapped. You gain two levels of exhaustion.
3	The waters protect you. A swirling wall of water encircles you, making you partially obscured. In addition, any creature that enters your space or grapples you takes 1d4 bludgeoning damage per round.
4	You gain the ability to speak with animals, as per the spell.
5	You gain the ability to breathe underwater.
6	You gain 5 temporary hit points.
7	You are lucky. Over the next 24 hours, you may reroll one saving throw, attack roll, or skill check. You must use the result of the second roll.
8	Your Wisdom increases by 1.
9	You gain a swim speed of 30.
10	You gain the ability to speak with plants, as per the spell.
11	You gain the ability to Wild Change once for up to 4 hours within the next 24, as per the druid, but only to a creature with a swim speed and a CR of 1 or less.
12	You are treated to a vision of the Eleven Profane Tides. Any spells you cast are as if cast 3 spell slots higher, and you have advantage on all saving throws.