I think that might be because of Unity Extras. 😅 Can you see if removing that pack fixes it?

Yeah, Extras is causing dark netherrack. Do you have OptiFine installed as well?

yes, i'm using optfine

I can replicate the same issue as well,
MC 1.16.5
Optifine preview_OptiFine_1.16.5_HD_U_G7_pre8

Temp fix : Deleting Unity-1.16.X-Extras-1.1.0\assets\minecraft\optifine\colormap\custom fixed the issue for now.

any word on when this fix might be incorporated into the curseforge release? specifically the 1.16.5 version

Oh.... yeah, it has been over a year now, hasn't it. 😅

I'll try to get an update for all Unity packs released sometime this month. Could be sooner... could be later.

While I do plan to update the pack, I don't see myself updating for older versions like 1.16.

You're more than welcome to edit the pack yourself using the fix that Kurosar listed above; it's a simple fix.

ah yeah i understand most aren't supporting older versions anymore, i think i can include an override with the fix for my modpacks. appreciate the quick reply!