Ghost Race

The Ghost is for players who survive a whole wipe while genuinely playing it — not someone who logged in once and vanished. The line is set in two steps:

1. Minimum-playtime floor. Drive-by visits are filtered out using Otsu's method— a standard technique for finding the natural split between two groups — applied to players' (log-scaled) playtimes. It finds the cut between casual visitors and real participants for this wipe, usually around an hour. Currently: players need at least 36m to be counted.

2. The line = the median. Among everyone above that floor, the qualifying line is the median(the middle player's playtime): half of genuine players are above it, half below. We use the median rather than the average because a few players with enormous playtime would otherwise drag an average far above what a typical player logs.

To earn the Ghost you must finish the wipe deathless with playtime above this line. The line drifts as the wipe goes on and more people play, so it's shown live.