[harm_unit]
                [filter]
                    [filter_vision]
                        visible=yes
#ifver WESNOTH_VERSION >= 1.11.0
                        side=1
#else
                        viewing_side=1
#endif
                    [/filter_vision]
                    [not]
                        side=1
                    [/not]
                    [not]
                        side=8
                    [/not]
                [/filter]
                amount=$random
                kill=yes
                animate=yes
            [/harm_unit]