Table of Contents:
- Ganon has the Triforce of Power. Zelda had the Triforce of Wisdom. Where is the Triforce of Courage?
- What is the Age of Chaos mentioned in the manual?
- Where is Link from?
- Where/What is the Underworld?
Ganon has the Triforce of Power. Zelda had the Triforce of Wisdom. Where is the Triforce of Courage?
As told in the AoL manual, the Triforce of Courage was hidden long before this time period. During LoZ, it is still resting in the Great Palace in the Valley of Death. When Link comes of age, it will be revealed to him that he is the one chosen to retrieve the Triforce of Courage.
What is the Age of Chaos mentioned in the manual?
It appears that, sometime before LoZ, the entire world entered an age of chaos or confusion. It is never made very clear what caused this chaos, or what the chaos consists of. AoL gives a clue. The age of chaos apparently didn't end with Ganon's death. His vile will lived on in his monsters, who awaited his return. Hyrule was on the road to ruin, because Ganon's minions were still causing trouble. So perhaps the Age of Chaos started when Ganon's evil began troubling the world prior to LoZ. This would make sense, because Ganon aims to take over the world and rule it with darkness and evil.
It seems that the Age of Chaos started before Ganon got the Triforce of Power. For Ganon invaded Hyrule and took the Triforce of Power while the world was in the Age of Chaos. So perhaps Ganon was causing trouble before he got the Triforce of Power, or perhaps the chaos was unrelated to him, and he took advantage of it. It certainly seems that great evil can be achieved in the world without the Triforce. Look at the Oracle games. The seasons and time itself were thrown into chaos. Perhaps the Age of Chaos began in the Oracle games. Which would make sense, since Ganon was revived at this time. But that depends on your time line theory.
Where is Link from?
This is never officially revealed. The only hint the manual gives is this: "During his travels [Link] had come across Impa and Ganon's henchmen." It is established that Link is a wanderer, but this says nothing about where he's from. Another hint is given in the AoL manual: "Meanwhile, Link remained in the little kingdom of Hyrule and lent his hand to its restoration." If Link stayed in Hyrule, one might say, this implies that he came from outside Hyrule, and stayed there. But this is not necessarily the case. This quote merely says that Link did not leave Hyrule. It does not say where he came from. After all, in OoT, Link came from Hyrule. But he left it. If I were to say that Link "stayed in Hyrule," this does not suggest that Link came from outside Hyrule. Rather, I'm just saying that Link didn't leave.
Many people think that Link came from a land called Calatia, and that his parents are Arn and Medilia. But this comes from the Valiant comics, which might not be reliable sources for true Zelda information.
Where/What is the Underworld?
There are several theories about this. Probably the best-supported theory is that the Underworld is literally a set of underground caves and caverns underneath Hyrule. In the Underworld are many dangerous labyrinths filled with monsters. The labyrinths are probably not connected together underground, which is why one must enter them via aboveground entrances. This is supported by the following quotes from the manual.: Page 5: "When Impa gave Link the order to destroy Ganon she also told him of the history of the land of Hyrule, and the layout of the nine underground secret labyrinths." Page 7: "The entrances to the underground labyrinths are hidden all over the place." Page 18: "The Underworld is a n underground maze of dangerous labyrinths."
There are other theories that equate the Underworld with the Dark World from ALttP, the Evil Realm from OoT, or the Evil Realm from the Oracle games. But these depend on your theory, and they aren't well-supported by LoZ itself.