Neat concept, could be actually stupidly fun when polished.
For now you have to deal with this:
___________________________________________
############################################################################################
FATAL ERROR in
action number 1
of Step Event0
for object obj_unit:
Variable obj_exit.<unknown variable>(100011, -2147483648) not set before reading it.
at gml_Object_obj_unit_Step_0
############################################################################################
--------------------------------------------------------------------------------------------
stack frame is
gml_Object_obj_unit_Step_0 (line -1)
called from - gml_Object_obj_unit_pawn_Step_0 (line -1) - <unknown source line>