Instructions
Go to Dugald Aisle near Dunbarton after talking to Krystell and using the "How to reach Tir Na Nog" keyword. Kill a black dire wolf.
Travel to Dark Eden and kill a werewolf in the Fiodh Dungeon.
Kill an ogre in the fields of Gairech Hill and return to Krystell.
Head for Tir Na Nog after Kristell gives you Red Wing of Goddess. You will have to wait until an actual Saturday to do this, as this is the only day you can go there.
Put the black pass on the altar to go to Barri Dungeon. Kill the enemies in this small area and then go straight to the treasure room.
Walk behind the statue of the goddess to find a hidden door. Open the door to enter Tir Na Nog.
Speak to Dougal and wait until half of the day has passed in the game. An owl will give you a quest from Dougal.
Kill 10 zombies in the graveyard and return to Dougal to finish the quest.
Purchase the Black Orbs quest scroll from Dougal after you have finished the Zombie quest. Read the scroll as it tells you how to complete the dungeon and then head to Alby Dungeon.
Complete the green dungeon, followed by the red one and finally the silver dungeon.
Put a green orb in the altar and collect the black orb piece from the treasure room in each orb dungeon.
Create the black orb from the pieces you gathered. Leave the orb on the Tir Na Nog Ably Dungeon altar.
Fight the monsters in the dungeon until you meet up with the Ghost Armor boss. Fight and defeat this boss.
Speak to Dougal after you emerge from the Black Orb Dungeon. Use the keyword "Glas Ghaibhleann's rebirth" in this conversation and Dougal will change the Goddess Pendant.
Go to Alby Dungeon and put the pendant on the altar.
Equip yourself with bandages and two powerful friends. Fight and defeat Glas Ghaibhleann and its monsters to beat the Mabinogi Generation 1 Quest.