This page shows pairs of heroes on opposite teams that were met the most. Higher deviation means that one hero is more likely to be picked specifically counter the other. Winrates and winrate differences are shown relative to the first (left) hero of the pair.
Deviation is difference between expected number of matches and the actual number (higher number is better and means the heroes are usually picked together intentionally, negative values mean otherwise). Percentage is how much of actual matches is the deviation number. Minimum match count for a pair is set to 2.