Simplify the following text for a Grade 10 native English-speaking person.
Original: While the Doctor 's other old enemies , the Daleks , were on the whole unchanged during the original series ' twenty-six season run , the Cybermen were seen to change with almost every encounter .
Simplified: While the Doctor 's other old enemies the Daleks did not change during the original series 's twenty-six season run , the Cybermen were seen to change with almost every appearance .