On this page of Assassin's Creed Valhalla's guide, you will find a detailed walkthrough for A Love Betrayed mission.
Eivor managed to find and save Tevdwr. It is time to meet with Cynon and get the whole truth out of him about what is happening in Glowecestrescire.
Rewards: 3400 XP.
Go back to Glowecestre (best to use the fast travel option) to question Cynon before the ceremony begins. Remember to remain anonymous and use the disguise.
First, go to the long house. Unfortunately, you will not find Cynon there so you have to look somewhere else. It is possible that someone has seen him.
Talk to Brigid, who is standing by the exit. Gwenydd, Modron's daughter, will interfere in the conversation. When you ask about Cynon, she will answer that he is busy preparing for the ceremony, but she can show you where he is if you agree to see her magic tricks. The girl will waste a lot of your time and you will have to find Cynon on your own.
Go outside and talk to the woman in the mask and you'll find out that it's late so Cynon went to church to pray. The man locked himself in and Geva has the key. There are two ways to get inside the temple.
Talk to a man standing near the longhouse. Go up to the table and pour him a beer. After he drinks a bit, you will be able to draw a lot of interesting information from him - stained-glass windows in the church are prone to damage so you can get inside the temple in this way.
In front of the church you will find the previously mentioned Geve. The woman won't let you go inside, but she has the key with her so you can just steal it from her.
No matter which option you use, enter the church to talk to Cynon. You will find him in the room on the left, behind the wooden boards.
Interestingly, Cynon will tell you that Modron will sit on the horned throne instead of him. It seems that the woman cleverly deceived Eivor and together with Cynon made him chase his own tail. It was she who planned to kill Tevdwr. The origin of Gwynedd will also come to light. When Eivor tells Cynon that Tevdwr has changed, the man will no longer want him dead and will tell you where Modron took the boy and what he intends to do with him.
Before you leave you can decide what will happen to the current ealdorman.
- Prepare to die: you kill Cynon right away, claiming he shouldn't be playing games with you;
- You'll die in the wicker man: you leave the Cynon to die during the ritual.
After the conversation, the mission will end and you will receive 3 400 XP as a reward.