In The Knife of Dunwall and The Brigmore Witches, stun mines contain two charges, and can be upgraded with a third. In Dishonored 2, they contain a single charge, and can be upgraded with a second and third charge.
The stun mine takes approximately two seconds to become armed once placed on a surface. This process is accompanied by a faint charging sound and a change of color from yellow to blue.
If armed stun mines are damaged before their charge is spent, they will turn red and then explode.
Stun mines target enemies, allies, and neutral characters alike.
The Chain Lightning upgrade in Dishonored 2 allows a single stun mine charge to take out multiple enemies near to the primary target.
As there is a delay between released bolts, a fully-upgraded stun mine is capable of taking out three groups of enemies.
A single blast from a stun mines overheat a Clockwork Soldier, causing it to shut down for a brief period. Two bolts is sufficient to kill one outright.
Stun mines are not triggered by Doppelgängers, allowing Emily to attach one to it and easily knock out groups of enemies.