Looking for inspiration - the lost tomb of Percival

Hi ! I am looking for inspiration for a saga in the welsh marches : my players are looking for the grave of Percival (Peredur actually), they have a general location (an area in south of Wales), they know that the tomb is in a forest "corrupted" by a dark faery (the Lord of Thorns) and I don't know how to make things intersting. Any suggestion would be welcome !


I know that I really struggled to draw up my first "dungeons" for ArM, but if you are curious, I have written both of them up.

An infernally corrupt fallen Flambeau Covenant.

A dragon infested cave network under a castle.