Crown of Netherese Binding
Wondrous item, artifact (requires attunement)
This crown was created by the most powerful arcanists of Netheril to combat the phaerimm threat. It appears as a circlet of mithral and adamantine with shimmering blue crystals that pulse with ancient magic.
Random Properties. The crown has the following random properties: • 1 major beneficial property • 1 minor beneficial property • 1 minor detrimental property
Magic Resistance. While wearing the crown, you have advantage on saving throws against spells and other magical effects.
Spell Turning. When you are targeted by a spell that requires an attack roll, you can use your reaction to reflect the spell back at the caster. The attacker must reroll the attack against its own AC or spell save DC.
Arcane Mastery. You can cast the following spells from the crown (save DC 18): counterspell, detect magic, dispel magic, globe of invulnerability, identify, and see invisibility. Once a spell has been cast from the crown, it can't be cast again until the next dawn.
Phaerimm Bane. When you are within 30 feet of a phaerimm, the crown glows with blue light, shedding dim light in a 10-foot radius. You have advantage on saving throws against the phaerimm's spells and abilities. When you hit a phaerimm with an attack, the phaerimm takes an extra 2d6 force damage.
Binding. As an action, you can target a phaerimm you can see within 60 feet. The phaerimm must succeed on a DC 18 Wisdom saving throw or be trapped in a shimmering prison of force similar to the spell imprisonment (no components required). While imprisoned, the phaerimm can't cast spells or use any of its abilities. The prison can be broken by a wish spell or by destroying the crown. Once this property has been used, it can't be used again for 7 days.
Destroying the Crown. The Crown of Netherese Binding is nearly indestructible, but it can be unmade if it is brought to the center of the ancient Sharn Wall and subjected to the combined magical attacks of at least three elder phaerimm simultaneously. This would likely require a temporary alliance with creatures that would normally never cooperate, making the destruction of the crown an event of cataclysmic significance.