Weapon EXP (abbreviated as WEx on this site) is a hidden weapon stat
that features from FE5 and
onwards. It is the main factor that
determines the rate at which weapon levels rise. Contrary to popular
belief, weapon Weight is not a factor (it is simply a
coincidence that weapons with high WEx values are heavy).
WEx is always 1 in FE5 (except for staves) and FE6, and is always 2
in FE11 (except for the real Imhullu and for Dragonstones, where it is
0). In FE7~10, different weapons and staves have varying values of WEx
(around 1~8). For
example, the Steel Axe (FE7/8) has a WEx value of 2.
|- to E
|E to D
|D to C
|C to B
|B to A
|A to S
|S to SS (FE10 only)
WEx explains how the Devil Axe, Hammerne staff and Eclipse
in FE7/8 increase weapon levels so quickly. It is because those three
have a WEx value of 8.
The lack of a fatal hit bonus explains why weapon levels are so
difficult to raise in FE5 and FE9. Compare to the GBA titles (which had
bonus) where you can easily get two S Ranks or one S Rank and an A Rank