Simplify the following text for a Grade 11 native English-speaking person.
Original: In their first appearance in The Tomb of the Cybermen , they resembled oversized metallic silverfish and had segmented bodies with hair-like tactile sensor probes along the base of their heads , which were topped with crystalline eyes .
Simplified: In their first appearance in The Tomb of the Cybermen , they resembled big metal fish and had segmented bodies with hair sensor probes along the base of their heads , which were topped with eyes .