Lisa

Access granted through the Rathleton Quest, where it can only be faced if it was the most voted one for the period. Talk to Flora to spend 1 voting right to enter its lever room. When the lever is pulled, a message will appear ("Everyone in this place will be teleported into Lisa's hideout in one minute. No way back!!!") and anyone inside the room will be teleported to the boss room after 1 minute. Be aware that when entering its lever room, you can not leave, teleport, or logout, and the only way to leave it is to pull the lever. The lever will only reset to its regular position after 16 minutes and 40 seconds have passed, so it is also important to not enter the lever room if it is not ready, or you will be stuck until the cooldown has passed. The fight itself is limited to 15 minutes.