'Card' as someone who might pull your leg? (5)
I believe the answer is:
tease
This clue is a double definition.
'card' is the first definition.
(synonyms)
'someone who might pull your leg?' is the second definition.
(a tease is someone who teases people)
'as' is the link.
(Other definitions for tease that I've seen before include "Banter, make gentle fun of" , "Josh" , "Torment, tantalise" , "Comb or card (wool)" , "Annoy good-naturedly" .)