Non-Exploding Hand Grenade

Origins
Hand grenades are old weapons, possibly used by the Byzantine Empire during the mid-700s, and mentioned by the Chinese during the time of the Song Dynasty. The modern hand grenade wasn't created until the early 1900s, where it went through some modern developments, most notably the safety features which keep the grenade from accidentally exploding.

It was seen in season 4 of Warehouse 13 (see below).

Effects
When thrown, the grenade fails to explode. It subsequently returns to the user, who experiences overwhelming guilt for participation in war, even if the user never participated in war in any manner.

Appearances in the Show

 * Instinct