The turrets are manned, the catapults are loaded and PopCrush's Royal Wars are officially underway—who will advance to the next battle?

This summer, we've pitted some of the entertainment world's biggest and brightest (...and youngest) against each other to determine which young man and which young lady should assume Hollywood's available pair of thrones. And now, it's time to decide whether Shawn Mendes or Austin Mahone would make a superior King of Young Hollywood.

In the first round, Mendes and his team of fans narrowly took down Troye Sivan's army by a 50.3 percent to 49.6 percent margin. Still, considering the Billboard No. 1 debut of Handwritten in April, we can't say we're terribly surprised. But could it be Mahone — whom Mendes has previously joined on tour — that ultimately cuts through his former ally's suit of armor?

One thing's for sure: the "Dirty Work" singer will be well-rested, as he defeated previous opponent Cody Simpson in a crushing 74 percent to 26 percent take-down. The single life certainly suits Becky G's former flame, but will it take him all the way?

Who can you see with a crown on his head? Tell us which guy has what it takes, and cast your vote between now and September 7 at 5 PM!

King Bracket Round Two

See these stars' advice to their past selves: