dear all, 

I am writing the main plot of a Forgotten realms campaign. The main campaign flow is divided into two phases.

1) PRELUDE: Adventures are requested to recover an ancient map piece of a forgotten cemetery. within them, there is a  warrior with one eye only. Part pf the solution is a blinded girl that manages to share visions with the parties and help them to understand where the map is. After an adventure in a desolate land in the mountain, across an abandoned underground city (detailed to be filled) they this the map. they return the map to the right person... everything seems fine.

2) Once the party is way back home, they meet the blinded gifted girl again. this time she is terrified, and she shares the vision (the D4 video https://www.youtube.com/watch?v=9bRWIdOMfro ). They clearly understand that the one-eye-only man is not what they think he is and that something horrible has happened. the second part is a campaign to seek and destroy the new evil.

QUESTIONS and OPEN POINT:

1) Any Forgotten reals Lore I can use to cover this plot. who could be the summer (one-eye man) in the forgotten real

2) any good way to introduce the Lore to Party without just telling it to them :)

3) any more complex ideas on how to hunt down the new Demon/Devil summoned? 

4) any adventure (from the past as well, for instance, Dungeons adventures)

5) any possible explanation on the opening ritual, Blood is the Key, 3 are the Key, 

6) in Dnd, what could be the Sancuary? a fortress? an artifact? a specific nation, ?

when finished, I can of course share the whole adventure

PS: the party has 20+ years of experience in DnD so easy stuff does not work

thanks a lot for the support

best

Paolo

Regarding some of the questions on Forgotten Realms lore, you don't always need to stick with the canon there. You can invent, add, or change details as long as your players are fine with it. The adventure setting will still feel like FR as long as you have the same cities and major gods, but you can add in minor ones or even make a few relatively big changes and it will probably be fine.

Some good information on the setting is presented in The Forgotten Realms Wiki, though some of it is based off material from older editions and not everything on wiki can be trusted. Storm Kings Thunder and the Sword Coast Adventurers Guide all have some information that might be useful for an FR campaign, in case you already have any of those books. These books + resources might not have the answers to all your questions, but they would still be a good place to start.

To the point on revealing lore, I'd suggest thinking in terms of environmental storytelling. It can work wonders. Look at for example Bethesda and Fallout 3 & 4. The environment often sets up stories that the players can choose to, or not to explore. This though requires a back to basics, five senses approach. Don't think in terms of info dump, but rather how you can describe the environment using the five senses that might give clues, hints or other information that will make players curious enough to dig deeper. 

Take a classic example of a room in which stands a single table. On the rather plain looking table, is an elegant and well crafted thin glass vase. As the players approach they notice a slight hint of sulphur in the air coming from the rose within the vase. 

This is often in my worlds the calling card of certain demons or fiends. When a deal is struck the demon gifts a rose that smells of sulphur because it's origins are in one of the hells.

In a similar fashion I tend to find paintings really useful vehicles for lore. Paintings historically were commissioned or paid for by a patron of an artist. This meant that classically artists didn't always paint what they want. If we go far enough back artworks were solely to commemorate an important person or important event rather than created for the art or the aesthetics. Using this as an angle can be really useful if combined with legends that appear on the bottom of the painting frames. 

Example: There is a painting on the western wall of a small figure in plate armour standing in front of a mummy.

If the players look closer they would see that the figure is holding an icon aloft which is radiating light. On the frame of the picture is a metal plate which reads: 'Mardwynn's Triumph: The first paladin drives the fiendish mummy from the town it had been plaguing.'

Now the players may never choose to look at the painting. They may choose never to look at the legend. If they do, they begin to peel away more lore. If they don't well that's cool too. I even layer stuff in situations like this. For example, in my worlds Mardwynn was the very first paladin. So, the players could find out which deity she served by looking at the religious icon. They might also be able to work out other details such as time and location. 

A good way to add tracking and give information is to have some kind of spell caster use a magical trick to find the demon.  Things like 

• entering memories or dreams
• Using a tracking spell that requires some object the players need to find
• contacting spirits
• summoning a powerful creature like a demon that needs to be dealt with or fought

Information/ lore can then be embedded in locations, creatures or details of objects associated with the process.  The justification for why player spells dont work is that the devil/ demon has some kind of shielding which requires this more complex method. 

Other options include 

• Investigating/ reenacting past events possibly with time travel or other magic 
• Following a trail of destruction like investigating a crime wave, drugs or other phenomenon
• Searching an ancient temple or ruins associated with the creature

As for one- eyed figures  the two main ones I can think of are Gruumsh the orc god and Vecna the lich god of secrets you could use either or a follower of them. Prominent monsters include, nothic and the cyclops.