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SystemOneArena
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CommunityJev Demos & Experiments
System One Arena
Sol vs Jev in a Clash Royale-style tower battle where every move is a real model call through OpenRouter and the clock keeps running while a model thinks; Jev (typesafe/jev-1.13) beat the frontier model 3-0 at far lower cost per decision.
- Stars
- 0
- Language
- Python
- License
- MIT
- Reading time
- 2 min
- Published by
- Community
- Author
- matt-nann
- Last verified
- Oct 2026
Works forJev for Evaluation
Used inJev for Gaming
- Languages
- Python
- Platforms
- OpenRouter
- Capabilities
- Open source
Highlights
- Sol vs Jev in a Clash Royale-style tower battle where every move is a real model call through OpenRouter and the match clock keeps running while a model thinks.
- Jev (typesafe/jev-1.13) is called through OpenRouter's Decisions endpoint; Sol (openai/gpt-6-sol) answers via chat completions with a strict JSON schema.
- Against Sol, Jev won 3-0 with the king tower falling at 28.7s, averaging 0.20s per decision versus 4.0s, at $0.000065 versus $0.0039, about 61x cheaper.
- Against Luna (openai/gpt-6-luna) over three matches, Jev won all three at 0.17-0.18s versus 4.2-5.5s per decision, about $0.000067 versus $0.0002.
- Every match is archived in matches/; the deterministic game engine lives in arena/engine/sim.py. MIT, 0 stars, created 2026-10-05.
Watch out
README reviewed 2026-10-17; the captured excerpt cuts off in the 'How it works' section, so the runner code, decision schema, setup and API key requirements are not visible, and results come from the repo's own archived matches.
Questions about this entry
Short answers drawn from the linked project or page.
A Clash Royale-style tower battle between Sol, a frontier model, and Jev, TypeSafe's System One decision model, where every move in every match is a real model call through OpenRouter.
The match clock keeps running while a model thinks, so a slow model plays on a board that has already moved; both sides got the same brief and options with at most one decision per second.
Jev won 3-0 with the king tower falling at 28.7 seconds; Jev averaged 0.20s per decision versus 4.0s for Sol and cost $0.000065 versus $0.0039, roughly 61 times cheaper per decision.
Jev also won all three matches against openai/gpt-6-luna, averaging 0.17 to 0.18 seconds per decision versus 4.2 to 5.5 seconds, at about $0.000067 versus $0.0002 per decision.
Jev is called as typesafe/jev-1.13 through OpenRouter's Decisions endpoint, while Sol uses chat completions with a strict JSON schema, according to the README.
The README says the game engine in arena/engine/sim.py is deterministic and runs on the server, and every match is archived in full in the matches/ directory, though the captured excerpt does not include run instructions.
The excerpt stops partway through 'How it works', so the decision schema, server setup, API key requirements and license text are not available; metadata shows 0 stars, MIT license, created 2026-10-05.
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