There are 34 King trading cards tracked on HobbyCardIndex, spanning Baseball, One Piece, Other. The most valuable is the King OP08-057 at $975.40 raw.
Source: HobbyCardIndex · Updated daily · https://hobbycardindex.com/players/kingKing Cards
34 cards · Baseball One Piece Other
All King Cards
King OP08-057
$975.40
King #1893
$107.97
King [Alternate Art] OP01-091
$88.80
King OP08-057
$56.98
King [Alternate Art Errata] OP01-096
$31.43
King [Chase] #1551
$28.49
King [Super Pre-release] ST04-004
$25.00
King [Alternate Art] OP01-091
$19.99
King [Alternate Art] EB04-031
$15.09
King [Alternate Art] OP08-057
$11.56
King #1551
$10.84
King [Alternate Art] OP01-096
$10.13
King [Errata] OP01-096
$8.87
King #1342
$8.85
King [Alternate Art] OP08-057
$7.00
King [Alternate Art] EB04-031
$5.71
King OP08-057
$5.10
King ST04-004
$3.99
King OP01-096
$2.29
King OP04-045
$2.19
King ST04-004
$1.85
King OP08-060
$1.75
King [Alternate Art] OP01-096
$1.69
King OP01-091
$1.54
King EB04-031
$1.45
King #SOS-14
$1.05
King OP01-096
$1.00
King [Errata] ST04-004
$0.62
King OP01-091
$0.61
King OP08-057
$0.47
King EB04-031
$0.19
King OP04-045
$0.15
King OP08-060
$0.14
King [Super Pre-release] ST04-004
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