What music is allowed

Hey,

I'm trying to choose a song for the credits of my game, and I chose "Warriors" froom Imagine Dragons. . But now I'm not sure wether it's even legal for me to use this, the game is a free game, and as far as I understood the things I read it should be ok as long as I credit them. I hope you can help me. Have a colourful day,

MRColourblock.

(P.S.: If this is not the eright place to post this, I wan't to aplogize)

(here's a link: https://www.youtube.com/watch?v=-8Ipi_YUbik )

The fact that it is a free game is irrelevant.  Unless they have specifically stated that the music is free for others to use you cannot touch it.  What is the full text relating to the use of this song?  At the end of the video it merely says that they "shared" this song.  That is not the same as saying that anyone else can use it in a game.

Your best bet would be to find some way of directly asking them, stating what you'd be using if for and that it would be used for a non-commercial project.