Terrain, Water system, and Grass: Sculpted and textured the mountain terrain in Terrain3D - grass, rock, and snow blending across the valley and peaks.
Built the river next. Wrote a mesh generator that traces a curve through the valley and extrudes a flowing ribbon along it. Took a handful of broken attempts before it actually generated cleanly.
Then grass. Built a scatter system that places blades across the terrain while avoiding steep slopes, the snowline, and the river itself. Fixed a transparency bug, fixed a sizing bug, and finally landed on 200,000 instances. The valley actually reads as a meadow now instead of a test scene.
The waterfall took the most work. Built it as a walk-under structure with layered falling water, billowing displacement, mist and splash particles, and spatial audio. Along the way I discovered my working files had been saving outside the actual project folder the whole time, which explained a bunch of mysterious broken paths. Ported in a proper wave shader, fixed a handful of Godot 4 syntax breaks, and got ripples, foam, and reflection all working. Also fixed a white-out bug so the water stays blue from most angles instead of blowing out to solid white when viewed head-on.
Last step was applying that same water shader to the river so everything matches. For the first time the world actually feels like a place instead of a pile of debug shapes.