Going to attempt to recommend a Neverwinter Nights mod for every day of December

Neverwinter Nights 1 is an older Bioware game that's been recently revitalised with an EE by Beamdog. It was notable for launching with an incredibly easy to use & extensive toolkit - intended for modders to create their own stories with

the campaign it shipped with is forgettable (though the expansions are better & I may get to some of them) but the toolkit was enormously successful & incredibly well-maintained, resulting in a plethora of excellent user-created campaigns, all available for free

Obsidian released a sequel some years later, with a much more sophisticated toolkit - that had a higher barrier to entry & so there's fewer success stories there but I'll look at a few (and the professional campaigns are a generally higher quality than the original's)

I could honestly talk forever about the flawed but ambitious Original Campaign for Neverwinter Nights 2 - and Mask of the Betrayer has easily the strongest narrative of any western rpg. If I run out of free modules I might come back to both of these

I would be remiss not to mention that Neverwinter Nights 1 in particular has not aged well in terms of looks; another tradeoff for the toolkit. The modularity of the design extended to visual assets which tend towards the blocky - the exteriors tend to resemble wedding cakes

Day 1: Almraiven https://neverwintervault.org/project/nwn1/module/almraiven

The ultimate necromancer-simulation. Almraiven is a city-adventure game where you are a necromancer investigating a series of grisly murders in a lushly realised Arabian Nights-esque setting.

With precious little combat, Almraiven plays out like a magical detective story - you'll need to learn the layout of the city, pay attention to the many vivid NPCs and follow up on clues off your own bat as you're drawn into a moody web of intrigue