Magic is not separate from the world—it’s part of it.
Core Rule:
Strong emotion + intent = change
Examples:
A joyful village might literally become brighter, more fertile
A grief-stricken forest may grow twisted and quiet
A determined hero can push beyond normal limits
Song is not required—but it is the clearest, most powerful form of expression, which is why it appears so often.
But some people are innately connected with magic that intent is enough, no song no strong emotion.