So I just had an odd thought.
Sabrina is really good at creating instruments out of Grief, right? Why don't we try to create a Witchy Grief Construct of the Ocarina of Time, and then test it out by playing either the Song of Storms or the Inverted Song of Time?
Surely the ability to halve the rate at which time flows will help us out immensely!
If that works, then (when there's no risk of accidentally triggering a Witchbomb), we should try pulling out a Grief Seed and playing the Song of Healing in order to copy some powers from dead MGs!