Off the top of my head, here's an alternative to the simple "rally" effect. My idea would have its best chance of working if Doug knows at least something about MHA, rather than hearing the song without any background or visuals.
In that case, it might give out more-or-less-random powers, for the song's duration, to everybody in the area of effect who Doug would consider basically good — allowing those people, for a little while, to indeed be metahuman heroes too.
It's already been shown that he has songs that give temporary powers (and one that powered someone up lastingly), but I can't recall if he has any that empower more than one person at a time.
In that case, it might give out more-or-less-random powers, for the song's duration, to everybody in the area of effect who Doug would consider basically good — allowing those people, for a little while, to indeed be metahuman heroes too.
It's already been shown that he has songs that give temporary powers (and one that powered someone up lastingly), but I can't recall if he has any that empower more than one person at a time.
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"The Lady of the Lake, her arm clad in the purest shimmering samite, held aloft Excalibur from the bosom of the water, signifying by divine providence that this was some killer weed."
"The Lady of the Lake, her arm clad in the purest shimmering samite, held aloft Excalibur from the bosom of the water, signifying by divine providence that this was some killer weed."