While we have the following in-game:
• Gold Mine for Farming Gold
• Tower of Despair for Farming EXP Potion
• Capitol Last Stand for Farming Runes
How about an 'Infinite Dungeon' which players can farm unique items that cannot be farmed from the story world map or even item summon?
How It Works
• Similar to the Gold Mine, there will be a limited number of turns to clear the mobs (3 creeps + 1 boss) and reveal the ladder to the next floor once the boss is defeated.
• Each different floor will be presented with a different challenge (e.g. Damage-over-time Boss / Healer Boss / Crowd Control Boss / Treasure Chest Boss).
• Upon defeating the bosses, a random dungeon exclusive item (e.g. armor / weapon / vanity item) will drop.
• Once the number of turns run out, the 'Dungeon Raid' will end.
• Dungeon entry is limited by event keys, just like Gold Mine / Tower of Despair / Capitol Last Stand.
Sources of Inspirations:
• Disgaea II: Dark Hero Days (Item Dungeon)
• Diablo III: Reaper of Souls (Greater Rift)