The Yklwa can be found in Tomb of Annihilation, page 32.
Bound into this weapon is a level 2 spell. The spell is determined when the weapon is created and must belong to the Conjuration, Divination, Evocation, Necromancy, or Transmutation school of magic. The weapon has 6 charges and regains 1d6 expended charges daily at dawn. While holding the weapon, you can expend 1 charge to cast its spell.
The spell's saving throw DC is 13, and its attack bonus is 5.
A yklwa (pronounced YICK-ul-wah) is a simple melee weapon that is the traditional weapon of Chultan warriors. A yklwa consists of a 3-foot wooden shaft with a steel or stone blade up to 18 inches long. Although it has the thrown weapon property, the yklwa is not well balanced for throwing.
If a weapon has the thrown property, you can throw the weapon to make a ranged attack. If the weapon is a melee weapon, you use the same ability modifier for that attack roll and damage roll that you would use for a melee attack with the weapon. For example, if you throw a handaxe, you use your Strength, but if you throw a dagger, you can use either your Strength or your Dexterity, since the dagger has the finesse property.