The vagrant who allegedly bludgeoned four sleeping homeless men to death in a pre-dawn Chinatown rampage Saturday calls himself “tranquil” on Facebook — but warns that he doesn’t play games.

“Yo soy un tipo trankilo,” suspect Rodriguez “Randy” Santos, 24, wrote on one of his three Facebook pages. But “no hay juego,” he added.

And in between tributes to Dominican rap music, and a profile video in which he appears to smoke a joint, he also appears to have been a fan of late evangelist Rev. Billy Graham.

As his profile picture on one account, he used a photo of a Spanish translation of Graham’s book “The Key to Personal Peace.”

His accounts list him as living in the Bronx, with connections to the Dominican Republic. At many points, his posts devolve into near gibberish.

His most recent post, from Sept. 3, said: “I’m a duck, sorry to my mom and friends,” in Spanish.

A stock photo posted in April has the caption: “loneliness kills,” also in Spanish.

Santos, who police said is homeless, was being held Saturday night at Manhattan’s Fifth Precinct, where he was facing murder and assault charges in what police called a random attack that left a fifth homeless man in critical condition, police said.

The unhinged maniac has 14 past arrests — four of them in the past year, a law enforcement source said.

He was busted in November 2018 for biting a man’s chest during a savage assault at a Midtown store, the high-ranking source said.

Santos’ last known address is a men’s shelter in Brooklyn, where he was arrested for attacking another man in May — with a metal object similar to Saturday’s weapon, according to sources.

He was also busted last March for groping a 19-year-old woman in Queens, the source said.