Are your rival LEGO® minifigures being bad and using poison gas? At first I was going to recommend that you give your troops these custom LEGO® gas mask/helmet combos, but on second thought, you should probably get yourself a custom LEGO® gas mask and investigate the source of that poison gas. Because, you know, minifigures can't actually move on their own. It's possible the poison gas came from someone cleaning with bleach and ammonia.
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