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 one notable exception.

Their blog details a conscious decision, starting in December 2021, to refrain from playing rogue-likes. Thunk explains this wasn't to improve the game's quality, but rather to embrace the experimental nature of their hobby: "Making games is my hobby; releasing them and making money is not. Naively exploring rogue-like design (especially deck-building, which I'd never done before) was part of the fun. I wanted to make mistakes, reinvent the wheel, and avoid borrowing from existing games. That might have created a tighter game, but it would have defeated the purpose."

However, this self-imposed rule cracked just once, a year and a half later. Thunk downloaded Slay the Spire. Their reaction? "Holy shit," they wrote, "now that is a game." The reason? Initially, they sought to study controller input handling in card games, but ended up completely engrossed. Thunk acknowledges that playing Slay the Spire earlier might have led to unintentional design copying.

Thunk's post-mortem offers many other intriguing insights. The game's initial working folder was named "CardGame" and remained so throughout much of development. The working title was "Joker Poker."

Several scrapped features are also detailed, including:

• A system where card upgrades were the sole method of character progression, similar to Super Auto Pets.
• A separate currency for rerolls, beyond the existing percentage-based system.
• A "golden seal" mechanic that returned played cards to the hand after skipping blind draws.

The number of Jokers (150) was also a result of a miscommunication during discussions with publisher Playstack. Initially aiming for 120, a later meeting resulted in a change to 150, a number Thunk ultimately preferred.

Finally, Thunk explains the origin of their name: a programming joke stemming from a conversation with their partner learning R programming. The phrase "local thunk," a reference to Lua variable declaration, became their developer handle.

Thunk's full blog post offers a much more in-depth look at Balatro's development. IGN, in their review, praised Balatro, awarding it a 9/10 and calling it "A deck-builder of endlessly satisfying proportions…the sort of fun that threatens to derail whole weekend plans."