How to remake an RTS game with Claude Code
ColCarlo99 used Claude Code to recreate Tzar in Rust and Bevy, one game system at a time. The developer compared play with the original while Claude traced discrepancies and helped build an internal test arena.
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Suggested prompt
Suggested prompt written by Agents In Use, not the source author. Replace bracketed inputs and review tool permissions first.
Using [code and game data I am authorised to inspect], help reconstruct [one game subsystem] in [language and engine]. Trace behaviour to the supplied material rather than inventing it. Add tests, document uncertain interpretations and keep session notes. Compare my play-test feedback against the implementation before moving to the next system. Preserve original-data and licensing boundaries.
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See placements →Evidence at a glance
Sourced account- Source poster / publisher
- u/ColCarlo99
- Original account
- Read the source ↗
- Published
- Source link checked
- Reported result
- The author reports a working Rust and Bevy remake that plays Tzar campaigns and random maps on Windows 10 and 11, supported by more than 600 tests. Public code and release documentation corroborate the project, but we did not run it.
- Human involvement
- The developer played the remake alongside the original, reported discrepancies and emphasised human judgement for visual bugs and varied campaign play. The process was collaborative, not a hands-off reconstruction.
A linked account supports attribution. It does not mean we independently reproduced its result.
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How the agent did it
- The developer supplied disassembled original game code and worked with Claude Code to reconstruct systems in Rust and Bevy.
- Claude ported combat, game AI, map generation and mission scripts one system at a time.
- The developer compared play against the original and reported differences for Claude to trace back to source behaviour.
ColCarlo99 used Claude Code to rebuild Tzar: The Burden of the Crown as ReTzar, an unofficial fan remake in Rust and Bevy. The developer reports working from disassembled original code rather than asking the model to guess the game's behaviour. A public repository documents the remake and links to releases that require a copy of Tzar.
The workflow proceeded one system at a time, including combat, game AI, map generation and mission scripts. The developer played the remake beside the original and reported differences. Claude traced those discrepancies back to the original code. The post reports more than 600 tests and memory notes between sessions to keep the work consistent. We did not run those tests ourselves.
In follow-up comments, the author explains that they also built an internal testing system called Tzar Arena, where multiple game AIs compete on random maps or preset missions. Human testing remained important for visual errors and less predictable ways of playing a campaign.
The stated outcome is a remake that plays original campaigns and random maps on Windows 10 and 11, with scaling up to 4K. Those capabilities are author-reported, not independently reproduced here. The repository identifies the project as unofficial and distinguishes its code licence from ownership of the original game data.
Who it's for: developers studying agent-assisted game reconstruction can inspect this example of incremental implementation with automated tests and direct human comparison.
Prompt
Suggested prompt (written by Agents In Use, not the author's)
Source: Reddit · u/ColCarlo99
Frequently asked questions
Did Claude reconstruct the game without human testing?
No. The developer played it beside the original and supplied feedback. Follow-up comments emphasise that people remained important for visual errors and unpredictable campaign play.
What is Tzar Arena in this account?
The author describes an internal testing system they created with Claude, where game AIs compete on random maps or preset missions. It supplemented human testing.
Does ReTzar include ownership of the original game data?
No. The repository identifies ReTzar as an unofficial fan project and requires a copy of Tzar. Its code licence does not transfer ownership of the original game data.
More details
Remaining steps
- The team used tests and inter-session memory notes, and built Tzar Arena for automated game-AI matches.
- The project released an unofficial fan remake whose users still need a copy of the original Tzar game.
About this account
Claude Code read disassembled code, ported game systems and traced reported behavioural differences while collaborating with the developer on tests.
Firsthand account by u/ColCarlo99: https://www.reddit.com/r/ClaudeCode/comments/1x8zh12/rebuilt_a_2000_rts_from_scratch_with_claude_code/. Public RSS post and returned comments captured on 20 October 2026; RSS coverage is partial. Body eligibility passed at 0.96. Results are author-reported, not independently reproduced. Suggested prompt by Agents In Use, not the author's original prompt. Linked repository README checked: https://github.com/ColCarlo/ReTzar.
Credit: u/ColCarlo99 on Reddit
Source published
Added to Agents In Use
Source checked
Tools and topics
Claude Code · Rust · Bevy · Tzar Arena · Disassembled original game code
game reconstruction · Rust · Bevy · coding agents · human testing
Editorial completeness: 100/100. Measures documented fields, not agent performance or verified outcomes.