I can't believe nobody has properly explained this.... anyway, "anthem", when used stylistically, means theme. For instance, if a venue, such as a dance club, has a contiguous design feel, it can be said that it sticks to an anthem.
Of course it can also mean a song that is used to convey underlying values, principles, spirit, commraderie, etc., eg. a national anthem.
1. The most brilliant japanese band ever (Loudness fans, you don't know what you're missing =3)
3. A official song you sing with pride that's mostly patriotic-
A game developed by BioWare, and produced by EA, release date scheduled February 22, 2019. Possibly a new step forward in gaming as we know it (And by that I mean battle royal games are old and we need something new).
Dude 1: "Hey did you hear about that new game anthem?"