Deltarune Chapter 5 features a song Toby Fox wrote 10 years ago, to his mother's disappointment: "Sorry Mom"

Deltarune Chapter 5 will release later this week, on June 24, a year after developer Toby Fox's last installment of his episodic role-playing game, though some people believe this new one could be more earth-shattering than anything Fox has done before. The fact that Fox has now revealed he's including a song in Chapter 5 he first wrote a decade ago helps this fan theory – though it doesn't aid Fox in earning his mother's respect.

"10 years ago I made a song that sounded like this," Fox writes in a Twitter post about a peacefully plaintive instrumental illustrated by Asgore's seven rainbow flowers, one of Deltarune fans' favorite subjects to speculate about. Encouraging more theories, Fox shares that his twinkly piano song is "called 'The Sunset of 7 Suns,' and "this is the hope for Chapter 5 from 10 years ago." Also, his mom doesn't love it.

"When I played this on the piano, my mom said 'you know, usually songs do more than just repeat…'" Fox recalls in a follow-up Twitter post. "Sorry Mom. Anyway, the version in-game sounds very different. Don't be surprised."

"Mama Fox would hate House music," one Deltarune fan accurately deduces. In any case, Deltarune sleuths are more preoccupied with analyzing every aspect of the song snippet Fox posted rather than interested in simply enjoying it with an afternoon tea and biscuit.

Some people are noting with fright that Fox's 10-year-old song sounds a bit like 'Finale,' a fan-favorite, optimistic melody from Deltarune 2015 companion game Undertale. Other Deltarune players are less interested in what 'The Sunset of 7 Suns' sounds like than they are in wondering why it was written a decade ago.

"Toby drops 'from 10 years ago' and everything else," nervously says one popular Twitter post. "Is this gonna be the most important chapter in the game."

It's certainly possible – but June 24 is arriving quickly, so try not to work yourself up with any more theories. We'll have our answers soon.

Toby Fox says Deltarune Chapter 6 is "developing well" and Chapter 7 may begin development "before the end of the year."