Shockwaves that do not use glowrings or images for their visual effects (e.g. the antimatter and graviton explosion shockwaves, and most other shockwaves in vanilla/VotG that aren't Domina shatter/circle of wrath, Iocrym manipulator effect, Ares nukes or Oracus harass) have bugged hit detection. While the first few hits with these shockwaves work as intended, future hits fail to register correctly and don't end up hitting ships.

See https://gfycat.com/AnxiousQuickHippopotamus for a GIF of this bug in action. Notice how the yellow shockwave (antimatter explosion, which doesn't use glowring or an image for shockwave effect) fails to register hits on the ICSs after it's used several times, while the Oracus harass shockwave (which uses an image effect) always hits correctly. Note that the antimatter explosion contains an area effect as well as a shockwave effect, so one or two hits register on the ICS (but not the large number of hits we expect from the shockwave, like the Oracus harass does).