..\data\maps\global\teutonic.order\map.grade.tree
Code:
[*] : struct.begin
template=crossbowman_inf
x = 0
y = 2
links : struct.begin
link=serjant_crossbowman_inf
armyexp=666
gold=666
struct.end
struct.end
[*] : struct.begin
template=serjant_crossbowman_inf
x = 0
y = 1
links : struct.begin
struct.end
struct.end
But campaign is not a problem. I test this unit in custom battles. If I make it works in custom it will probably work in campaign too.