a double-edged sword

something that causes both advantages and problems His great intelligence was a real double-edged sword because he never felt he could communicate with ordinary people.

Common Names:

Name	Pronounced	Usage
Wilburg	-	Anglo-Saxon
Capucine	ka-puy-SEEN	French
Morpheus	MAWR-fee-əs (English)	Greek Mythology
NİDa	-	Turkish
Burnham	['bɜ:nəm]
Knud	KNOOD	Danish