Tougher Fights: NPCs inside the dungeon are 2x stronger.
Bigger Rewards: To make up for the difficulty, they give 3x more SP!
Shared Loot: It doesn't matter who lands the killing blow, everyone gets the full reward! This is the perfect opportunity to team up and boost your friends.
The Portal has a 30 seconds join phase, after those 30 seconds pass everyone in the portal will join the dungeon and a new join phase begins immediatly.
To be able to join the dungeon you need a dungeon key. The key will drop from any Grassland and Cursed Kingdom boss with a specific chance (you find them in the Mobs Section of the bosses in each area).
You have a 5% chance to get a Perk Stone I from normal mobs and 100% chance to get one from bosses.
That means you can get an average of 6.6 Gem Stone I each dungeon (ty Xofiu)