Development level

Development level is a gameplay mechanic in Xenoblade Chronicles 2 which serves to measure the development of Alrest's nations. Each inhabited Titan has its own development level, starting at level 0, which can be raised up to level 5. To raise a nation's development level, a certain amount of dev points must be acquired for said nation.

A nation's development level can be checked while at a shop or in the Merc Group menu, symbolized by stars. However, the amount of dev points obtained is hidden and cannot be viewed.

Dev points
Many actions done while in a nation's area will yield a certain amount of dev points, including:
 * Completing regular s - Most quests started in a nation will usually reward dev points for this nation, with some exceptions such as Nopon of Good Tastes.
 * Completing Merc Missions - Every Merc Mission will award dev points for the nation they are given in.
 * Selling and buying items at s - Selling and buying items at a nation's shop will award dev points depending on the price.
 * Discovering s, s and Secret Areas.
 * Talking to s - Talking to any NPC with a yellow star next to their name will award some dev points.

Effects
Raising the development level of a nation offers some perks:
 * Prices at shops and inns will be discounted by 10% for each development level, meaning that all items will be half off at development level 5. This does not affect the amount of gold given by item trading shops or the price of the Inherited Core Crystal.
 * Some Merc Missions require a nation to be at a certain development level to unlock.
 * Some NPC dialogue will become available after reaching certain development levels.

Leveling up the first nation
The way to raise the first nation to development level 5 is mostly the same as earning gold through salvaging. Exchanging at item trading shops gives a good amount of dev points along with gold that can be spent on more cylinders, which in turn award more dev points. As such, this is better done during or after, with the help of Golden Cylinders, though it can be done at an earlier point with Silver Cylinders at a slower pace. For this reason, the first nation to reach dev level 5 while using this strategy is usually Mor Ardain, as Golden Cylinders become available when reaching Alba Cavanich.

Leveling up all other nations
Once one nation's dev level has reached level 5, the most effective way to raise the other nation's level is to buy items in the former and sell them in the latter. This is done because the discount at shops from reaching dev level 5 will divide by half any item's price, making it equal to its sell price. Therefore, items can be bought at this nation's shop and sold at another nation's shop to recoup all costs and gain dev points there.

This strategy is usually done during and after Chapter 4, with Golden Cylinders, due to them having a high price along with the fact that 99 of them can be carried at a time, unlike pouch items. This allows for the raising of the target nation's dev level in a few trips.