Flaming Mirror of Tenh

The Flaming Mirror of Tenh is a silvery, oval-shaped magical item approximately six feet in height and three feet at its widest point. A planewalking wizard, enamored of the Elemental Plane of Fire, created this item in order to provide easy access to her favorite plane. As a Magic Action, the mirror becomes a portal from the Elemental Plane of Fire to Oerth and vice versa. When you create the portal, roll a d20. On a 5 or lower, 2d4 fire elementals appear within 30 feet of you. They are Hostile to you and your allies. The portal closes after 1 hour or earlier if you close it as a Bonus Action. When you close the portal, roll a d20. On a 1, the mirror is drained of its magic and shatters.