In their YouTube video reviews, Brendan Jowett, Nate Herk | AI Automation and Bijan Bowen compared Claude Opus 5.5 with GPT-6 Astra on game-building tasks. Jowett favored Opus’s visuals across five games. Herk chose Astra’s $8 museum game over Opus’s $31 build, but preferred Opus’s $60 one-prompt educational world to Astra’s $12 version. Bowen judged Opus’s C++ skate game definitively better than Astra’s.
Nate Herk’s museum game: Astra wins on time and cost
Herk asked both models to build a browser game about escaping a miniature museum after closing. The request called for three connected rooms, an inventory, five linked puzzles, contextual hints, sound controls and an ending.
Opus built a dark museum with a story, music, a flashlight and objects to examine. Herk found the graphics and realism decent and the experience immersive. The mouse control felt odd, though, and Herk did not work out how to escape.
Astra’s version centered on puzzles, with clues, a journal and a code-locked cabinet. Herk solved the cabinet clue and found the game easier to enter and develop through further prompts. Astra took 34 minutes and cost about $8; Opus took an hour and a half and cost $31.
Herk chose Astra for the museum escape because it was faster, cheaper and easier to iterate on. That choice did not erase Herk’s appreciation for the quality and immersive approach of Opus’s game.
Nate Herk’s educational world: Opus wins the one-prompt result
For a second game-building task, Herk requested a three-dimensional world based on 100 recent videos, with concepts users could explore. Astra built a first-person world containing rooms, experiments and quizzes. Herk found parts confusing and the experience harder to understand than expected.
Opus built a third-person world with themed rooms and interactive simulations. Herk was impressed by its demonstrations of token prediction, in which a system generates the next piece of text, and agent loops, in which it repeats steps to carry out a task. Balls sometimes got stuck in one simulation, but Herk preferred the quality of Opus’s one-prompt result.
Astra took 45 minutes and cost $12; Opus took an hour and 44 minutes and cost $60. Herk asked whether iterating on Astra’s world until it cost $60 would produce a better result than Opus’s, and answered that they would argue yes. Of the worlds produced from one prompt, Herk chose Opus’s.
Brendan Jowett’s five games: Opus pulls far ahead visually
Jowett compared the models on a platform game, a race, a spaceship battle, a shooter and a boss fight. Opus’s graphics and assets drew emphatic praise across the five builds, while the games differed in cost and how they played.
In Rampart, a two-dimensional platform game, Astra’s running, jumping and double-jumping worked without glitches during Jowett’s playthrough. Jowett faulted its bright colors, background, assets and on-screen interface. Opus delivered similar mechanics, but Jowett rated its lighting, textures, character animation and interface much higher. Jowett completed the Opus game and said the visual difference was stark: “The result is honestly like night and day”. Opus cost about $48 against Astra’s roughly $23 and took about twice as long.
In the Apex Circuit racing game, Astra delivered working driving and drifting. Jowett found its car much faster than the other racers and criticized its interface and some scenery. Opus’s assets, effects and interface looked much better to Jowett, and its car speed was more comparable with the competition. Both builds reached a victory screen. Jowett noted loud audio in Opus’s race, then compared the roughly $63 Astra build with the $67 Opus build: “The cost of building the game through Opus was practically exactly the same as building the game through Astra”.
In Void Wing, Astra’s spaceship could fly, shoot enemies and finish the mission, though Jowett found its models and textures basic. Opus’s ship, asteroid textures, music and sound effects impressed Jowett much more. Jowett rated Opus’s graphics and gameplay a million times better than Astra’s, regarded the result as an epic game and called its 3D modeling the main difference between the builds. Opus’s interface, however, was similar to Astra’s and fell short of those in some of Opus’s other games.
Dead Signal, a first-person shooter, was playable in Astra’s version, and Jowett liked its lighting. Some enemies stood idle, and its interface needed work. Opus’s loading sequence, lighting, weapon and enemy detail, and sound design made a far stronger impression: Jowett thought it looked like a legitimate game that they would not have guessed was AI-made. Jowett also found it difficult to play. Astra cost about $32 and Opus about $50.
In the Colossus golem boss fight, Astra’s build had an assembling animation and graphics Jowett thought looked good. Its golem model and mechanics disappointed Jowett, who could not work out how to defeat it. Opus added rain and ground-breaking effects, and Jowett praised its loading screen and presentation. Jowett died repeatedly and was unsure whether the difficulty reflected the mechanics or Jowett’s own play.
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Bijan Bowen’s skate game: Opus earns a clear preference
Bowen showed Opus’s C++ skate game, praising its New York City feel and pointing out the water effects, lighting, camera options, pedestrians, fire escapes and skateboarding mechanics. “That was sick”, Bowen said. Bowen’s review includes a sponsor segment.
Bowen thought the car models looked poor, encountered an invisible wall and could not grind on one rail. Those problems did not change Bowen’s comparison: Opus’s skate game was definitively better than Astra’s.