Home News Local Thunk Didn't Play Any Roguelike Games During Balatro's Development...Except Slay the Spire

Local Thunk Didn't Play Any Roguelike Games During Balatro's Development...Except Slay the Spire

by Camila Mar 16,2025

Balatro developer Local Thunk recently shared a fascinating development history on their personal blog, revealing a surprising detail: they avoided playing most rogue-likes during Balatro's creation, with only one exception.

Their development timeline shows a conscious decision in December 2021 to abstain from playing rogue-likes. Thunk explained, "Making games is my hobby; releasing and profiting from them isn't. Naively exploring rogue-like (and especially deck-builder) design was part of the fun. I wanted to make mistakes, reinvent the wheel, and avoid borrowing from existing games. A tighter game might have resulted, but it would have defeated the purpose of what I love about game development."

PlayHowever, a year and a half later, this self-imposed rule cracked. Thunk downloaded *Slay the Spire*. Their reaction? "Holy shit," they wrote, "now *that* is a game."

The reason? "I was having trouble with controller implementation and wanted to see how they handled controller inputs for a card game, but I got sucked in. Thankfully, I avoided it until now; otherwise, I surely would have copied their incredible design (intentionally or subconsciously)."

Thunk's post-mortem offers many other intriguing insights. Early development saw the project folder named "CardGame"—a name that stuck. The working title, for much of development, was "Joker Poker."

Several scrapped features were also detailed:

  • A system where card upgrades were the only upgrade path, similar to Super Auto Pets' leveling system.
  • A separate currency for rerolls, outside of the percentage-based system.
  • A "golden seal" mechanic that returned played cards to hand after skipping all blinds.

The number of Jokers (150) stemmed from a miscommunication: "I told Playstack (the publisher) about '120 Jokers' in October 2023. Later, someone mentioned 150. I couldn't recall if I'd said 150 or they misheard, but 150 seemed better, so I added 30 more."

Finally, the origin of the name "Local Thunk" is a programming anecdote:

"My partner was learning R and asked, 'How do you name variables?' I ranted about casing, descriptive words, etc. She said, 'I like to call mine thunk.' I thought that was hilarious. Lua uses 'local' to declare variables, hence 'local thunk' was born! I didn't use it as a handle for a while, but that's where it came from."

Thunk's blog post offers a much more detailed account of Balatro's development. IGN awarded Balatro a 9/10, calling it "A deck-builder of endlessly satisfying proportions...the sort of fun that threatens to derail whole weekend plans."