Someone at the Obsidian's official forum found some of the upcoming Margran's Fire challenge info:
Challenge The Gods: Complete the game with a God Challenge enabled. (5 new game points)
Challenge The Pantheon: Complete the game with all God Challenges enabled. (10 new game points)
Diplomat: Complete the game without killing any kith. (5 new game points)
Expert Mode: Complete the game on Expert Mode. (2 new game points)
Holy Crown: Complete the game on Expert, Trial of Iron, and Path of the Damned with all God Challenges enabled. (20 new game points)
Holy Crown Solo: Complete the game on Expert, Trial of Iron, and Path of the Damned with all God Challenges enabled while not taking any Companions. (20 new game points)
Naked Run: Complete the game without wearing any armor, boots, gloves, helmets, or accessories in combat. (5 new game points)
No Rest for the Pro: Complete the game with fewer than 10 rests. (5 new game points)
Path of the Damned: Complete the game on Path of the Damned Mode. (5 new game points)
Trial of Iron: Complete the game on Trial of Iron Mode. 5 new game points)
Triple Crown: Complete the game on Expert, Trial of Iron, and Path of the Damned modes. (10 new game points)
Triple Crown Solo: Complete the game on Expert, Trial of Iron, and Path of the Damned modes while not taking any new companions. (10 new game points)
Zero Knockouts: Complete the game without any party members falling unconscious during combat. (5 new game points)
Seems like no achievement for "finish the game on Expert, Trial of Iron, and Path of the Damned modes while not taking any new companions and without wearing any armor, boots, gloves, helmets, or accessories in combat." though.