But the problem is that the "Wagon Steel Armor" can only be upgraded to Level 3 at most.
From Level 3 to Level 6, there's a long gap in between.
Unless one can find a large amount of iron ore and develop silently without caring about anyone, it's entirely possible to do so, but for most people, it's impossible, so they can only replace defense and attack accessories as their level increases.
But...
The Constant Star Train doesn't need to.
It only needs to keep upgrading its "armor," which costs less, and defense accessories are expensive to upgrade, especially higher quality ones, making them even more costly to upgrade.
The armor effect is even better.
It blocks both direct physical attacks and energy attacks, and with "Permanent Shock Absorption," unless they're extremely high-level monsters, it's basically impossible to cause any damage to the train.
But he still crafted all three accessories, after all, to upgrade to a Level 7 train, these accessories must be crafted.
