Dark Souls
41 Achievements
1,000
80-100h
To Link the Fire
Reach "To Link the Fire" ending. Details for this achievement will be revealed once unlocked
90
How to unlock the To Link the Fire achievement in Dark Souls - Definitive Guide
If you light the bonfire, you will get the "To link the Fire" ending; If you decide to turn your back and walk away without lighting the bonfire, you will get the "Dark Lord" ending.
Each ending nets you a separate, 90 point achievement.
This specific achievement relates to the "To Link the Fire" ending.
Before crossing the door to his room, feel free to apply any useful buffs you might have - the stamina-boosting grass or Replenishment miracles might be wise.
As far as actually fighting him, you can either attempt to parry several of his types of blows (you'll probably know how to do this by the time you get here), or you can just bring a lot of pyromancer spells with you, especially if you have Quelana's ascended flame, and burn him to a crisp. Oh, oh, I'm sorry - to "Cinders".
Good luck with New Game +!
The trick was, saving the game exclusively on the usb stick. After defeating Gwyn, I placed myself in front of the bonfire. Now just the moment before I activated it I pulled the usb stick out and watched the ending. After the ending the achievement popped and the new game plus started.
I then loaded my savegame from the usb stick and just did the other ending by walking away.
As this solution corrupted someone's savegame: Make sure that while you pull the stick out the savegame flame does not show up because this might destroy your savegame. I think you can avoid this if you pull it out right after the game quicksaves as it saves regularly. Do not move and after pulling it out immediately press A to start the ending sequence.
Here is a link to a full walkthrough of the game with full commentary. It began as a pyro focus build to help new players break the game early, but a Black Knight Halberd drop changed that. Either way, this is an efficient path through the game that any gamer can emulate.
NOTE: This was recorded from console and DOES NOT have the new DLC included. My channel however has boss videos against all the DLC bosses.
http://www.youtube.com/playlist?list=PLTaOHX8kEkD4Uh62ZXtLsc...
Hope it helps
When you defeat Gwyn in the Kiln of the First Flame, simply light the bonfire and the trophy is yours.
Once you have filled your Lordvessel with all four souls of the great lords you can challenge the game's final boss. You can either talk to Frampt, the serpent in Firelink Shrine or, if he isn't there anymore, you can simply jump on the hole he used to be and you'll reach the area Kiln of The First Flame, the last one of the game.
At the end of the area you will find the fog door leading to the final boss. Before going through make sure you have done everything you wanted to do in this playthrough because after you beat him you'll inevitably be thrown into New Game+.
After beating him you'll have two choices of endings. To acquire this trophy simply light the bonfire in the center of the area and end the game.
Check the bosses and covenants sections for more information on them.