n. In a computer game, a list of the enemies that a player has killed.
2007
Plenty of online games emphasise the slaying of other players, many going so far as to include killboards allowing blood-thirsty junkies to tally and compare their kill ratios.
1998
The Rec Room features the familiar killboard, which lists current kills for all Midway squadrons.
1997 (earliest)
But after three bomb runs that scored enough to get me somewhere in the top ten bomber scores on killboard, I defected to Az and made life merry hell for the two yahoos flying bombers.