Ruled by Madness is Chapter 16 of Fire Emblem: The Sacred Stones. At the end of the chapter, Eirika and Ephraim can promote to Master/Great Lords at the player's choosing. If you choose not to promote them, they will receive the Lunar and Solar Braces, respectively, which can be used in the item menu to promote. They will also acquire Sieglinde and Siegmund, the Legendary Twins of Renais.
The enemies this chapter will vary based on the route you took. In Eirika's route, most enemies will be fighters, mercenaries, and other physical units. In Ephraim's route, most enemies will be magic users. Also, Orson's weapons will change. In Eirika's route, he has a Spear and Silver Sword. In Ephraim's, he has a Runesword and Silver Lance.
Your starting point also changes depending on the routes. In Ephraim's route, you start at the southwestern part of the map. Eirika's starts at the southeast, near the stairs.
- Red Gem (Sage in throne room)
- Turn 12: Thief from the north east (the opening south of the set of three chests)
- Once you get close to the Warriors to the north east or the passage to the throne room, from the south eastern entrance, the Warriors will begin to move. Also enemy reinforcements will appear before your next turn begins: 4 Cavaliers and 6 Great Knights appear from the south east and south west, and a Thief from the north west
- If you wait long enough, a Thief will appear in the northeast.
- Turn 6: Thief from the south west (stairs to the right of the Warrior/Mercenary group)
- Turn 16: Thief from the north east (the opening south of the set of three chests)
- Once you get close to the Knight to the north east or the passage by the south eastern stairway, some of the castle guards begin moving and enemy reinforcements will appear a turn later: 4 Cavaliers and a Great Knight appear from the south east. Also if you get close to the throne room, or the Warrior/Mercenary group to the south west, the Warrior/Mercenary group and the Druids will begin to move.
- Another group of reinforcements will appear one turn later: 2 Sages (one of them drops Purge) from the north east and 3 Rangers and a Valkyrie from the southeast. The warrior drops a Hero Crest.
- Orson has battle conversations with both Eirika and Ephraim, but they are locked to the respective Lord's route. Ephraim's conversation won't play on Eirika's route, and Eirika's won't play on Ephraim's route.
- Differences from the Japanese version:
- The map layouts for Eirika and Ephraim are reversed: Ephraim's map has more magic users, and Orson has a Runesword and Silver Lance. Erika's map has more physical units, and Orson has the Silver Sword and Spear. However, unit starting positions are consistent between both versions of the game. Ephraim's route still starts on the far left side of the map, while Eirika's starts near the stairs.
- The Sages in the throne room were given Elfire and Divine tomes in the English version.