I believe it has something to do with the fog of war and missing your target. I was shooting at a hunter pair once that, for whatever reason, my wolverine just couldn't hit. It was running away on the edge of my sight, so the wolveriene would drive, 5 feet, shoot some rockets, drive another 5 feet, etc. for over half the map until it finally hit/killed the thing. It was funny to watch, but pretty annoying at the same time. I wanted that hunter dead!
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