Here is the full list of all 60 Shadowgate achievements worth 1,000 gamerscore.
Unlocking all achievements
Successfully beating the game and defeating the Warlock Lord for the first time.
Completing Master mode in 1000 turns or less.
Completing Journeyman mode in 2000 turns or less.
Completing Apprentice mode in 2700 turns or less.
Curing yourself of a curse in 500 turns or less. Master mode.
Curing yourself of a curse in 650 turns or less. Journeyman mode.
Curing yourself of a curse in 800 turns or less. Apprentice mode.
Uncovering 100% of the map locations and notes.
Uncovering 80% of the map locations and notes.
Uncovering 50% of the map locations and notes.
Examining 600 different items in the game.
Examining 500 different items in the game.
Examining 400 different items in the game.
Experience 48 unique deaths.
Experience 35 unique deaths.
Experience 25 unique deaths.
Solving 62 major puzzles.
Solving 50 major puzzles.
Solving 40 major puzzles.
Completing Master mode in one game session.
Completing Journeyman mode (or higher) in one game session.
Completing Apprentice mode (or higher) in one game session.
Completing Master mode without the use of hints.
Completing Journeyman mode (or higher) without the use of hints.
Completing Apprentice mode (or higher) without the use of hints.
Praying at every altar.
Successfully casting every spell.
Successfully creating all of the recipes in the lab. Master mode.
Killing nine different goblins.
Winning the game without killing any goblins. Master mode.
Consuming 22 edible/drinkable items.
Using every weapon.
Finding and lighting every torch.
Successfully completing the Black Axe quest. Master mode.
Wearing all of the wearable items.
Picking up 200 different items.
Beating the game in all three difficulty modes: Master, Journeyman, and Apprentice.
Discovering all special deaths. Master mode.
Collecting 10 torches.
Finding Lakmir the Timeless.
Discovering and entering the inner castle.
Discovering and entering the catacombs beneath the castle.
Showing mastery of the weather outside Shadowgate.
Finding two relics from another place and time. Master or Journeyman mode.
Appeasing your traveling companion with all his requests.
Tidying up the castle of dust and spider webs. Master or Journeyman mode.
Finding all 5 relics described in the prophecy.
Attempting to communicate with all skulls.
Summoning Lakmir and gaining each of his instructions.
Catching all elementals.
Reading every book.
Burning every item that can be destroyed by fire.
Mining all crystals in the catacombs. Master or Journeyman mode.
Lighting and observing the signal fire.
Successfully completing the Dread Pumpkin Quest. Normal or Apprentice mode.
Successfully completing the Dread Pumpkin Quest. Master or Journeyman mode.
Winning the game on Ironman mode (no saving). Apprentice mode.
Winning the game on Ironman mode (no saving). Journeyman mode.
Winning the game on Ironman mode (no saving). Master mode.