Originally Posted by Doug5150

Revenge? Okay.

You need two bowls. In one, you put a half-and-half mixture of portland cement powder and flour, in the other, you put plain water. The rats eat the concrete/four, and then get thirsty and drink the water. The concrete solidifies in their intestines in about 12 hours.

You'll want to remove any you find however--after ~3 days when they have died, but before they totally start rotting....
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