| Even if everything has been predestined, will you not oppose it?|
This page contains spoilers pertaining to the plot or storyline of this game. Read on at your own risk, especially if you haven't played this game!
|Tephra Cave, with a Brog in foreground|
|Skip Travel Points||7|
|Exits To|| Colony 9|
|Mutually Exclusive Sidequests||0|
|Appears In||Xenoblade Chronicles|
Tephra Cave is the first cavernous area of Xenoblade Chronicles, but it is a large cavern in terms of scale and scope. To reach both destinations, the Cylinder Hangar and Bionis' Leg, it will take two separate trips.
This network of caves is the primary route between Colony 9 and Colony 6, along with other parts of the Bionis. A squad from the Defence Force is permanently stationed within the complex, and the area outside the Cylinder Hangar is often used for training.
 First Trip
The Colonel has tasked Reyn with gathering Ether Cylinders to restore power to the Mobile Artillery that crashed into a house in Colony 9's Residential District. The Cylinder Hangar itself, along with parts of Mag Mell Ruins, appear to be part of a larger ship, one that Shulk believes to have been made by Homs.
The first trip is a passing through to reach the Cylinder Hangar, but that doesn't mean there aren't sidequests to pick up!
 Journey to Bionis' Leg
After the Mechon attack Colony 9, a door in Mag Mell Ruins that was sealed previously has now opened. Shulk and Reyn utilize this new path to go towards Colony 6. Along the way, they happen upon some dead travelers, who appear to be traders from Colony 6. They decide to "return the dead travelers to the Bionis," leaving their corpses in a body of water.
They decide to take a rest, and after Shulk nods off he hears a mysterious voice, asking him "Even if everything has been predestined, will you not oppose it?" The vision abruptly ends when he sees monsters around him, and Reyn's shouting helps to snap him back into reality!
After proceeding a short while further, Reyn gets captured from above in what appears to be ginormous spider silk. Shulk realizes that his most recent vision involves a big spider that is going to kill Reyn, scaring him at the thought of losing another friend. After a lengthy chase, he catches up with Reyn and tries to warn him by getting him to run towards him, but Reyn doesn't; he runs towards what appears to be daylight.
In an act of desperation, Shulk swings the Monado while it shows a new symbol, unlocking Monado Shield and saving Reyn from certain death! Together they kill the oversized arachnid and safely get out of the cave. Shulk then comes up with a theory: those visions are meant to be a warning of some kind. Case-and-point: the vision he had of the Arachno Queen killing Reyn, and his actions that led to stopping that vision from coming true.
Outside the cave, on the Bionis' knee, there's a view of the Mechonis, far off in the distance.
 Post-Mechonis Core
After the events that take place in the Mechonis Core, a new, previously unexplorable part of Tephra Cave opens up. This new path runs from Vilia Lake to the Arachno Nest, and contains a ruin of the Giants. However, the enemies are all Level 90 and up.
- NOTE: Not all locations shown on this map can be reached right away, as many of them are inaccessible until after the events of Mechonis Core.
 First Trips
 Post-Mechonis Core
- Earth: Within the Forgotten Cave
This Ether Deposit can be seen the first time you pass by, when trying to reach Reyn. However, you cannot reach it until after Mechonis Core.
- See Tephra Cave/Sidequests for further Sidequest details
 Story Enemies
 Quest-Exclusive Enemies
 Early Quests
 Post-Mechonis Core
 Additional Enemies
- See Tephra Cave/Monsters for a complete list of Monsters in Tephra Cave, along with Unique Monsters.
- See Tephra Cave/Collectopaedia for full details of the items that are in the Collectopaedia.
- The Legend of the Spider
- Glowing in the Night