Magical Teardrop

''And remember, kids: your sadness carries a special magic power. SO HAND IT OVER.''

When somebody sheds a singular teardrop whose supernatural energy is Plot Convenient enough to Save The Day. The teardrop itself is not necessarily an Ex Machina as it's a natural happening, unlike someone suddenly showing up out of the sky to save their friends from Sudden Death. However, its magical properties can be considered such.

If the Magical Teardrop is enough to bring someone back to life, that's Revival Crying.