People often say that musicians "come out of nowhere" or that they're "overnight successes" even though they've likely been toiling away in their small scene for ages with some local recognition (think Andre's verse in "Elevators (Me & You)"). It's often just that they got bigger than they used to be, usually on the strength of one hit (a perfect example is Juice WRLD's "Lucid Dreams").
Xander 850, though, really has come from nowhere. His website is just a photo of him, hand on chin, looking pensive with links to all his Soundlcoud, Youtube, Facebook and Twitter. His only song that I could find anywhere is the one released yesterday with Rich The Kid called "Light It Up." He has come out of complete internet silence, save for one one Instagram post celebrating his signing with Republic Records, to debut this song, a simple banger about telling "that chick to light up" (ie. get lit).
Quotable Lyrics
Bandana, was jumpin the fence
Diamonds on me I'm a prince
Fuck that I'm a king
Ice up on the ring
Bad bitches love the bling
Three hoes on the screen