After a weeks delay we closed the campaign this evening.
Gryvorn proved far more deadly than I expected.
For clarification - The heroes were Leofric of the book (necromancer), Syndrael (Knight), Avric (Disciple), Jain (Wildlander).
In the first turn the heroes gathered search tokens (yielding healing potions and a random shop item - Glaive from Trollfens). Except Jain who used her heroic ability to move close to Gryvorn, fire off two shots with the Trueshot bow and retreat round a corner.
In the first overlord turn I played Dark Charm on Syndrael who brought Avric down to half health. The Baron moved fired a shot and missed.
I moved Gryvorn forwards and was able to Reach Jain causing potentially a lot of damage which got converted to full fatigue plus using all defences available. I then played Reinforce at the end of the turn to place a minion shadow dragon on the map (behind Gryvorn).
Then Leofric raised a zombie which was sent to attack Gryvorn- causing no damage, then army of undeath which caused no damage. Avric used radiant light to heal himself and Jain for two health and cause two damage to Gryvorn. I then spent my token for Gryvorn to attack Jain hitting her for 11 damage, pierce 2 before she could reset her defences on her turn. Hero down! Importantly the hero with big hitting ranged damage and the ability to cause overlord cards to be discarded.
This shocked the party and I expected that to be the high point.
Syndrael then fatigue advanced hitting Gryvorn for a lot of damage and stun, missing on the second attack.
Overlord second turn - Gryvorn retreated behind the shadow Dragon - the baron fired an ineffective attack and the shadow dragon stayed put rather than closing with Syndrael and getting hit by Guard.
Without Jain the party were unable to rely on ranged attacks wiping out the shadow dragon. Avric used a less effective ranged weapon to get the shadow dragon down to 2 remaining health. The zombie missed the Shadow dragon due to the Shadow ability. Syndrael then closed on the shadow dragon using his heroic feat bring Avric with her. Syndrael killed the shadow dragon and advanced onto Gryvorn causing a lot of damage with his first attack, but missing on his second. Gryvorn was now down to 3 remaining health.
On the final overlord turn Gryvorn attacked playing Wild Energy (unstable Forces Plot deck) to gain an additional surge at the risk of being defeated if no damage was caused by the attack. With 3 surges the attack meant Syndrael, Avric and the Zombie were hit for 10 fire damage, pierce 2. Avric was felled and the Zombie dropped into a burning heap. Syndrael was badly scorched, surviving on 1 remaining health, used her Deflecting shield to further damage Gryvorn who was on 2 health.
The Baron then closed on Syndrael for a melee attack slaying the third hero. In her dying moments Syndrael used her Stalwart ability to land the death blow on Gryvorn.
So in the end a lonely Leofric fled the burning castle to recant how his brave companions gave their lives to protect Terrinoth.
All players were left enthused and I was very happy to have three Hero scalps after a very tense last session. I was pleased the heroes won the campaign after all their successes - a total party kill would have felt wrong.
Gryvorn was definitely Not a mere Shadow Dragon.
I had expected the party to use Syndrael as a guard while Jain used ranged attacks to kill Gryvorn and the baron with Avric healing everyone and Leafric sending in a steady wave of zombies.
Luckily Jain allowed me an opening which I was able to exploit. The reinforce card really came into its own, with the party agreeing that Gryvorn was clearly labelled a Master Shadow Dragon for the quest.
A long post basically to say that the finale was not the whitewash I had feared and we really enjoyed it.