GPT-6 Astra Is INSANE For Building Video Games (Full Test)

Summary
In this review video, Brendan Jowett tests OpenAI's GPT-6 Astra model to evaluate its ability to autonomously build video games. Using OpenAI's Codex agent application configured to "Ultra" mode alongside Unreal Engine 5 and Blender 5.2 LTS, he prompts the model to recreate progressively complex games ranging from Super Mario Bros. to Subway Surfers, Counter-Strike 2, Minecraft, and a Grand Theft Auto VI-inspired open-world prototype.

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What is shown

• Setup & Workflow [00:46]: Walkthrough of the software requirements: OpenAI Codex desktop application (running GPT-6 Astra Ultra), Unreal Engine 5, and Blender 5.2 LTS for 3D asset generation.
• Super Mario Bros. Recreation [01:55 - 05:25]:
  • Initial prompt asks for a 1:1 recreation of 2D Super Mario Bros. inside Unreal Engine [02:07]. The resulting playable clone is demonstrated [02:26].
  • Discussion of how Astra initially pulled open-source sprite and audio assets from three GitHub repositories [03:41].
  • A follow-up prompt requires the game to be built completely from scratch without external assets [04:15], producing a newly textured and scored version titled "Super Mario From Scratch" [04:20].
• Subway Surfers Recreation [05:27 - 08:59]:
  • Prompt requesting a 3D portrait endless runner recreation without third-party libraries [05:35].
  • Demonstration of the functional gameplay featuring track obstacles, coin collection, power-ups, HUD, and an in-game pause/settings menu [06:04].
  • Inspection of the generated 3D meshes (character, train, barrier, coin) inside Blender [08:13].
• Counter-Strike 2 / "Dustfront" [09:28 - 12:30]:
  • Prompt for a 1:1 recreation of CS2 desert town map ("Dust II" style) [09:28].
  • Demonstration of "Dustfront", showing deploy menu, first-person weapon handling, functional bot combat, bomb planting zone, and pause menu [09:37].
• Minecraft / "Blockworld" [12:31 - 15:33]:
  • Prompt for an open-world voxel recreation in Unreal Engine 5 [12:38].
  • Gameplay showing block placing, breaking, flight mode, animal entities (pigs and sheep), and procedural infinite terrain generation across hills and water [12:51].
• GTA 6 / "Neon Coast" [15:47 - 18:33]:
  • Prompt for a coastal open-world Miami recreation inspired by GTA 6 [15:49].
  • Showcase of "Neon Coast", featuring third-person walking, entering and driving a sports car with speedometer HUD, urban traffic, sunset lighting, and weapon mechanics [16:02].

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Claims & numbers

• The presenter claims GPT-6 Astra is OpenAI's newest and most powerful model, and that he ran it on "Ultra" mode [00:05, 02:03].
• The presenter states each test was prompted with brief instructions (roughly five sentences) without using external open-source libraries (aside from the initial Mario run) [00:32, 06:48, 14:54].
• The Codex UI reports the model's work duration for each build:
  • Initial Mario clone: worked for 1m 58s across 21 files [01:55].
  • Scratch Mario clone: worked for 26m 5s across 21 files [04:14].
  • Subway Surfers runner: worked for 11m 44s across 27 files [05:27].
  • Dustfront (CS2 clone): worked for 13m 20s across 30 files [09:28].
  • Blockworld (Minecraft clone): worked for 18m 55s across 31 files [12:31].
  • Neon Coast (GTA clone): worked for 16m 20s across 29 files [15:47].
• The presenter claims the Minecraft recreation includes fully working infinite procedural terrain generation created by the AI [14:04].

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Notable quotes

• [00:03] "Today I'm putting OpenAI's newest and most powerful model, GPT-6 Astra, to the test, building games like Grand Theft Auto, Minecraft, Mario, and more."
• [02:36] "And I do have to confess that I think GPT Astra actually cheated in building this, and I'll get to why in just a second..."
• [06:47] "...literally from five sentences be able to build this entire game."

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Assessment
This is an independent creator review and hands-on capability demonstration showing the Codex desktop interface, Unreal Engine 5 playtests, and Blender asset inspects. While the prototypes exhibit expected visual glitches and rough animations typical of raw zero-shot generative builds, the video convincingly demonstrates playable, interactive game prototypes generated via GPT-6 Astra.

Described by gemini-3.8-flash on 2026-09-29 from the video's audio and frames.