Crash fixed. Some players had the King boss crash when it both died and teleported at the same time resulting in :
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FATAL ERROR in
action number 1
of Step Event0
for object obj_boss4_teleport:
Unable to find any instance for object index '424' name 'obj_king_parent'
at gml_Object_obj_boss4_teleport_Step_0
############################################################################################
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stack frame is
gml_Object_obj_boss4_teleport_Step_0 (line -1)
Sorry for the inconvenience!