Here is the correct syntax for a single schema IMPDP rename :
impdp system/**** directory=DATA_PUMP_DIR dumpfile=export_something.dmp logfile=imp.log remap_schema=name:newname
How would you import multiple schemas from one export while remapping them? Will this work?
impdp system/**** directory=DATA_PUMP_DIR dumpfile=export_something.dmp logfile=imp.log remap_schema=name:newname,name2:newname2,name3:banana