Units on doodads/units

[LegendaryViewer]

Hey guys I was wondering how can I make units walk on doodads like I've seen on other maps example a castle wall or a tower. Second how do I attach a unit on another unit example a boat and units are standing on it like the ones I've seen on the credits on warcraft 3 reign of chaos where orcs are actually riding an orc ship. THANK YOU FOR YOUR TIME MUCH APPRECIATED <3

 

[EdgeOfChaos]

Try changing "Is Walkable" to true in the destructible editor. Or add the classification Walkable in the Unit Editor.

 

[Wietlol]

Do you have experience with JASS/vJASS?
Cause if so, then I have a solution for your second thing.