It’s probably just an accident of scheduling, but this deeply affecting documentary is arriving just when there’s a debate raging at the school gates about children’s use of smartphones and social media. So while it’s undoubtedly troubling how tech platforms set out to addict and exploit young minds, The Remarkable Life of Ibelin provides a fascinating counterargument about how online gaming at least can be a lifeline for some individuals who find themselves isolated in the real world, or IRL as the kids like to say.

Born in 1989, Mats Steen started out like many other Norwegian children of his generation: energetic, sweet-natured, unusually pale. However, his parents Robert and Trude soon discovered that he had Duchenne muscular dystrophy, a genetic condition that eroded his ability to move and breathe and which would eventually kill him at the age of 25. By that point in 2014, Robert, Trude and Mats’ sister Mia knew that Mats spent hours of his life online playing World of Warcraft using special equipment to accommodate his disability and had been publishing a blog about his life.

Then they signed on to the blog to announce his death, thinking hardly anyone would read it – and a flood of emails came back, for it turned out that Mats, who had been logging into Warcraft by the name Ibelin and using an able-bodied red-haired (yet still notably pale) avatar, had built up an extensive network of friends over the years. Ibelin had courted women in this digital world, and was even a bit of player at one point, but more importantly he was deeply liked for his kindness and empathy. His sage advice had helped a mother and her son (a young man with autism) build their own relationship in Denmark through online interaction, for example. Mats may have spent most of his time alone (apart from health workers and support staff) in a flat upstairs from his family, but WoW gave him a community.

Using the archive which recorded thousands of words of interactions between Mats/Ibelin and his friends, the film recreates Ibelin’s digital life, using animation in the style of WoW. This means the whole gamut of fantasy-character physiognomies, in all colours, shapes and sizes – except that they all have chunky thighs, disproportionally engorged forearms and, if female, enormous bosoms. But scoff all you like, you non-gamers, because by the end it’s nearly impossible not to shed a tear after the touching finesse and shape of this story, capped with a near-perfect pan across the multi-species gaggle of digital friends gathered around Ibelin’s modest grave to pay their respects.

• The Remarkable Life of Ibelin is in UK cinemas from 18 October and on Netflix from 25 October.