Don't know must it be JASS but...
Event: Hero reaches level X
action: An dialog menu apears where you can choose next hero. After choosing a new hero apeares at position of old one. All items comes from old hero to new.
EXAMPLE:
-Riffleman
/
footman
\
-Knight
Event: Hero reaches level X
action: An dialog menu apears where you can choose next hero. After choosing a new hero apeares at position of old one. All items comes from old hero to new.
EXAMPLE:
-Riffleman
/
footman
\
-Knight