Bahseth's Spiritual Slave

Bahseth's Spiritual Slave can be cast as a reaction on one humanoid creature no greater than large size that dies within 60 feet of the caster. The spirit raises from the body of the humanoid creature and tethers up to 200 feet to the diamond material component the caster is using. The spirit cannot move further than 200 feet from the diamond it's been tethered to, however, can still shift in and out of the ethereal plane. For all intents and purposes, the spirit is considered a Ghost from the Monster Manual and can utilize all of the abilities and actions described. On casting the spell the spirit must make a Wisdom Saving Throw against the caster's spell DC, if the spirit succeeds its spell save the spell fails, the spirit disappears and the diamond shatters into dust. If the spirit fails it's spell save it's compelled to do it's new masters bidding and can roll for initiative order if in combat. After 24 hrs the spirit will make another Wisdom Saving Throw against the caster's spell DC. If the spirit succeeds it will become hostile towards the caster, If it fails it becomes permanently under the control of the caster. If the spirit is destroyed so will be the diamond and vice versa, the spirit cannot destroy the diamond.