One is a 29-year-old Swedish YouTube star who considers himself the most famous person on the internet. The other is an Indian entertainment company founded by a former fruit-juice seller who worked the streets of Delhi.

Quite how and why PewDiePie and T-Series became locked in a “war” might seem a mystery to those used to the analogue age. Online, however, the race to become YouTube’s No 1 channel of 2018 has been an intensely fought battle – and one with bizarre offline consequences.

Last week the Wall Street Journal’s website was hacked with a post urging readers to subscribe to PewDiePie’s channel. The post claimed to offer an apology on behalf of the paper for “misrepresenting” its reporting last year on allegedly antisemitic and racist content in PewDiePie’s videos.

Speaking to the BBC, Bhushan Kumar, the 41-year-old managing director of T-Series and heir to his father’s business, claimed: “I am really not bothered about this race. I don’t even know why PewDiePie is taking this so seriously. He’s getting his people to push him, to promote him. We are not competing with him.”

The growth of T-Series, a record label and film production company that uploads Indian film songs and clips, has been feverishly recorded online. Bollywood superstars signed to its roster have rallied fans to help topple PewDiePie’s five-year reign as the most-subscribed-to channel on YouTube.

Bhushan Kumar, whose company T-Series is rapidly making up ground on YouTube. Photograph: Raajessh Kashyap/Hindustan Times

Yet PewDiePie, whose real name is Felix Kjellberg, also has powerful guns. Last month, fellow YouTube millionaire “Mr Beast” bought commercial hoardings and radio ads in his home city of Greenville, North Carolina, to support him. Meanwhile, another YouTube celebrity, Justin Roberts, conducted a similar publicity stunt by buying a $1m billboard in Times Square, urging New Yorkers to subscribe to PewDiePie.

One fan claimed to have hacked hundreds of thousands of internet-connected printers worldwide to automatically print out messages rallying support for PewDiePie’s campaign. Dozens posted the evidence on social media. “Attention!” reads the desperate call to action, “PewDiePie is in trouble and he needs your help to defeat T-Series!”

To date, Kjellberg has amassed 77 million subscribers on his platform – more than Taylor Swift and Ed Sheeran combined. Last month, the near-daily filmed vignettes of his life playing video games and performing skits, primarily popular with 18- to 24-year-old men, had been watched 19bn times. T-Series and its satellite channels, meanwhile, garnered 4bn views but, according to video analytics firm Tubular Labs, is growing at around 120,000 subscribers each day to Kjellberg’s 20,000. Despite explosive growth, and with just days left, the Indian challenger is trailing by some 1 million.