docs: add gameplay preview and Codex credits

Co-authored-by: Codex <codex@openai.com>

README.md

@@ -31,7 +31,7 @@ tags:
 [![llama.cpp pipeline](https://img.shields.io/badge/pipeline-llama.cpp-orange)](https://github.com/ggml-org/llama.cpp)
 
 > ### 🙏 Credits
-> - 🤖 **Made with [Codex](https://github.com/codex)** — used heavily across game code, dataset generation, docs, fine-tuning workflow, model iteration, and some asset creation (the `BOSS` and `rune_goblin` magic-circle assets are Codex-generated).
+> - 🤖 **Made with [Codex](https://github.com/codex)** — used heavily across game code, dataset generation, docs, fine-tuning workflow, model iteration, frontend design, asset placement, asset creation, and map design. I'm not a frontend dev; Codex helped make the custom UI and RPG world feel playable and polished (the `BOSS` and `rune_goblin` magic-circle assets are Codex-generated).
 > - 🧠 **Models by [OpenBMB](https://huggingface.co/openbmb)** — [`openbmb/MiniCPM-V-4.6`](https://huggingface.co/openbmb/MiniCPM-V-4.6) (fine-tuned spell engine + base dialogue/story).
 > - ⚡ **Thanks to [Modal](https://modal.com)** for fine-tuning credits.
 >
@@ -52,6 +52,10 @@ existing/procedural game assets.
 
 See [`rune_goblin_plan.md`](./rune_goblin_plan.md) for the full design doc.
 
+<p align="center">
+  <img src="./merged.gif" alt="Rune Goblin gameplay preview" width="900" />
+</p>
+
 ## Architecture
 
 ![Rune Goblin architecture](./Rune_Goblin_ARCH.png)
@@ -373,6 +377,11 @@ extra Tiny Swords assets (terrain tiles, colored buildings, resource piles,
 skulls, animated flames/TNT goblins) and the snow/stone/dead-tree recolors that
 give each biome its own ground and props.
 
+Codex also designed the custom frontend experience and helped place assets,
+create generated assets, and shape the RPG maps. I am not a frontend developer,
+so its help covered both the UI polish and the practical layout work needed to
+make the world readable in play.
+
 - **Terrain & buildings**: [Tiny Swords](https://pixelfrog-assets.itch.io/tiny-swords) by **Pixel Frog** (CC0).
 - **Creatures (enemies/NPCs)**: Basic magical animations pack — elementals,
   golems, witch, treant, fairy, pixie, necromancer, sorceress, druid, wisp.