I'm looking for ideas on how to stat a monster I'm making for a one shot. The monster is visually based off of the Jöttun, the monster in the 2017 film The Ritual. The monster is connected to one of my PC's (Gloom Stalker Ranger) backstory and is a source of fear for them that they (and the rest of the party) will have to face in a dark forest.
I'm not so much looking for a direct one to one conversion of the monster from the movie into D&D 5E, just using the monster (and Mini) as a base for the main boss monster of my one shot.
The monster's origins are going to be related to a curse inflicted on it for committing cannibalism and it's curse causes it to have an insatiable bloodthirst. I wanted to ask for some ideas around building a monster that utilized the Frightened condition heavily and possibly inflict some kind of bloodthirst or confusion onto the party. I want it to act as a solo boss monster for an encounter, against a party of 5, 10th level PC's with a decent amount of magic weapons/items. I was looking for pretty deadly encounter to challenge the party and also wanted to throw a few minions at them before the actual boss encounter, unsure of what monsters I could use for minions (leaning on undead or possibly monstosities), and also wanted some ideas on what minions it might surround itself with.
Apologies for not knowing the artist for the specific image, but I believe Keith Thompson was the original designer for the monster in The Ritual. I'll link his website (with more design art of the Jöttun) in a comment below. The monster does not necessarily need to be exactly CR 14 but my estimate is that is the highest CR I'll want for a solo boss encounter. Any help, ideas, or full stat blocks would help alot.