Einar, who was in his laboratory, drank some herbal liquor while working on a mechanism to create a simple mine.
To begin, he created a wooden base in which he installed a simple button which, once pressed, could work a mechanism.
Because of the dangerous nature of mercury fulminate, he only started testing it using small glass jars of water.
The system was too simple; it was placed on the ground and when the enemy pressed the button on the piece of wood, the vial with mercury fulminate would start to create a reaction that would make it explode.
Because the dynamite would be for crossbow and ballista ammunition, the mercury fulminate could only be used as an explosive.
Although it was not very powerful for the amount that each mine would have, it could create an explosion powerful enough to blow up a foot.