Nightfall is one of the bigger quest lines in Elderan. This quest line is a replacement of the tibia 7.4 Pits of Inferno quest line. The quest can be divided into pre-quest and main quest.
Pre-quest
Mission 1: recover the 4 map pieces
Head to the Plains of Havoc, east of the temple. You will find an underground base that will lead you through 4 tunnels. Your goal is to recover 4 map pieces and return them to the Cursed soul. Once you have gathered the all parts and talked to the NPC you will be able to enter the upper deck and sail to Nightfall. When exploring the ruins, you will face different type of monsters (e.g. demons, black widows, executioner, ...) and you will have to solve several small puzzles.
Note: you will need 2 persons to recover one of the map pieces.
Mission 2: sailing to Nightfall
After you gathered the 4 map pieces and talked to the cursed soul you can enter the upper deck. Make sure to gather enough people as you will have to face several waves of demonic creatures. You do not need 10 people but a small group is advised. Once you are ready, click the steering wheel to start the raid! You can position yourself strategically on the right side of the ship. The event is time based.
Main quest
Mission 3: arrival on Nightfall
Once you finish the raid you will be able to talk to the Cursed ghost and travel permanently. Your next task is to talk to the Nightfall guard and ask about a key. You can find him guarding the entrance to Nightfall city on the southern bridge. Make sure to have 1 ham with you. This key will give you access to the Crypts on the southern part of the island.
There are several crypts, your goal is to explore the correct one until you meet the Nightfall priest. He will reward you a Vial of Water and explain you how it works. He will also tell you to close the first mini portal. Be prepared to face a single misery.
Mission 4: Library portal
The library portal is located through the center of Nightfall city. You need a crowbar to break the front door. You will face several possessed books, blazing skulls, elder beholders and black widows. You will have to solve a small mini puzzle to be able to exit through the backside of the library. There you will meet Mefisto who will give you access to the secret passage if you provide him 30 demonic spirits. This is a good hunting spawn for Warlocks or if you want to farm the mini boss Apprentice of Urnas. Make sure to have a talon with you to leave.
Mission 5: Walls portal
The portal is located on the southern walls of Nightfall city on the 2nd floor. You will have to face several harpies, black widows, blood bats and watchers. This is one of the easiest portals.