We Built a Castle Siege Game with GPT-6 Astra!

## What we actually built We used GPT-6 Astra with Higsfield, Blender, and GDAU to make a castle siege game called Ashfall: The Last Gate. The setup is simple: describe what you want in ChatGPT, let Astra generate images and models, then open the result in GDAU and play it. No coding needed.

The playable loop is already there. You hold right mouse to draw a bow, aim, and fire on an army, then fall back to the keep as walls get overrun. Objective timers and torchbearer targets give you a reason to shoot specific enemies. That part works.

## The parts that needed real fixing The first version was a wall and a lot of empty ground. No castle. So the workflow became: play the game, screenshot problems, circle them in yellow, and tell Astra what to change. We asked for a bigger keep, taller defenses, mountains behind it, and a staircase built into the side. Astra made those changes, and we went back into GDAU to check.

Some problems were visual. Cade, the player character, wasn't holding the bow right. The arrow didn't line up. His quiver floated around his hips. We fixed the equipment in Blender and adapted movement from GDAU's demo assets. He still runs like he's out for a jog, not surviving a siege, but it's better.

Other fixes were about clarity. The first playtest left you wondering what to do. Astra added a timer and objective text, so you always know the current goal. We also cut a constant background hiss that sounded like static and replaced it with footsteps, arrows, and nearby fighting.

## What still needs work Combat needs more weight. Arrows should hit harder, and defenders should shout warnings when runners get close. The retreat could use more soldiers falling back around you and louder attack audio behind you. Wall fights and Cade's movement are the next pass.

The Higsfield connection is the part worth copying. Describe a shield concept, get an image, refine it, then turn it into a 3D model. That's how we made Cade: generate a character image first, fix the outfit (one attempt gave him a modern padded jacket), then use that image to build the model.

Astra works for this kind of prototyping if you're willing to keep sending screenshots with yellow circles and checking the result in GDAU. It's not a one-prompt full game, but it's a real playable loop.