Mistpiercer is the 25th most-used weapon under the current filters (1.3% of 280,903 recorded fights), winning 58.5% overall - 14.4% of its wins come against better-geared opponents.
Best against Heavy Mace (93.8%), Iron-clad Staff (93.1%), Great Arcane Staff (91.7%). Struggles against Lightcaller (22.2%), Forge Hammers (23.3%), Spirithunter (30.0%).
Winrate by IP difference (50-IP buckets, dot size = sample size). A flat curve means the weapon carries regardless of gear; a steep one means it only wins when out-gearing.
