Venthyr’s final mount , Desire’s Battle Gargon, comes from the Ember Court, from The Countess tribute at the end of the scenario.
The mount comes from the Ember Court.
You must upgrade the building to Level 4 to unlock The Countess as a guest.
Unlocking level 4 from scratch takes 28,500 Reservoir Anima and 80 Redeemed Soul.
While the mount was obtained at Ember Court Level 5, level 4 is likely enough if you don’t want to upgrade your Court to 5.
Next you must invite The Countess to Ember Court sessions until you reach Best Friends with her.
This process takes 8 Courts without counting rep bonuses like Darkmoon Faire or Noblegarden’s Ember Court Bonuses.
After reaching Best Friends with her, you must invite her an additional time and end the Court with her mood at Very Happy or Elated to receive the mount in her tribute chest.
None the Wiser Guild 