The world map is a large hex grid broken into tiles. Tiles have a variable life before de-spawning. New tiles spawn on the right side, hence the map gradually expands rightward. Typical new tiles have about 3 weeks (31 days) of life before expiring.
Note that the hex column a tile is in doesn't indicate how much time is left, two tiles directly in a vertical line will have different decay times. So the burn horizon is inconsistent.
Moving between tiles is most effective to travel on Walkers and costs Purified Water which must be stowed in the walker's hold. Walker water hold sizes, in effect, limit the range a given player may go in a single "trek". Water efficiency declines over longer trips.
The Tiles are divided into a few categories with various statistics like difficulty and clan caps. Difficulty indicates the relative difficulty of the mobs on the tile but becomes less useful for calculating other things. Ultimately knowing the tile type by it's image is the most useful way of knowing what resources will spawn there and whether it's worth a visit at the time.
General Tile types:
- Cradle Tiles (Easy)
- Desert Tiles (Medium)
- Themed Tiles (Hard)
- Ephemeral Tiles (Hard)