"The last stronghold of the elven rebels is like a tumor in the forest. It must be uprooted."Forest Fortress is a dungeon which unlocks at level 30. Its drops are Iseer shards, Elf Prophet and other Epic cards, 40 gold, Steel and Magic Essence. It requires 25 stamina in total.
Round 1 faces Tiana with 65 HP who spams Pegasuses and has the weapon "Destroyer" 3MP: Give target unit +2-3 Attack and Armor Piercing. All damage is physical, so armor isn't a bad idea. Enemy units are: Pegasi Scout, Pegasi Charger, and Pegasi Captain.
Round 2 faces you against Head Priest Fyero and Elite Ranger Riego. They both start at 50 HP. Fyero has "Blessed Staff", 3MP: All units minions +1 or +2 HP. Riego has "Double-Strike" which is 3MP: Deal 2 PDMG to all enemy units. They go enraged when the other dies, and will spam their weapon unlike when they're unenraged.