Sulla described bug - I saw it today but it would work with special conditions:
1. enemy unit has to enter range and left it (considering range on that screen line infantry would have to ran at least 350 metres (300 metres x 2 - at leats 125 x 2 = 350 metres).
2. your units starts firing
3. enemy leave range
However despite bug mentioned - 2 or 3 shots of 1 light infantry unit would not kill 50% of heavy infantry unit
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