We can genetically modify a rat to be the same body temperature as a humans, then parachute in several thousand rats into enemy territory. These rats will pick up the enemies advanced warning and intrusion sensors by way of heat signature.

The enemy, thus thinks they are a division of troops with heavy armament trying to hide, perhaps interpreting these signatures as thousands of troops with all but a little of their skin showing. Think of the Predator movie where Sylvester Stallone was being hunted by the alien for sport. When