Emags now have a ten-use limit.

code/game/objects/items/weapons/cards_ids.dm

@@ -54,6 +54,14 @@
 /*
  * ID CARDS
  */
+
+/obj/item/weapon/card/emag_broken
+	desc = "It's a card with a magnetic strip attached to some circuitry. It looks too busted to be used for anything but salvage."
+	name = "broken cryptographic sequencer"
+	icon_state = "emag"
+	item_state = "card-id"
+	origin_tech = "magnets=2;syndicate=2"
+
 /obj/item/weapon/card/emag
 	desc = "It's a card with a magnetic strip attached to some circuitry."
 	name = "cryptographic sequencer"
@@ -61,6 +69,56 @@
 	item_state = "card-id"
 	origin_tech = "magnets=2;syndicate=2"
 	var/uses = 10
+	// List of devices that cost a use to emag.
+	var/list/devices = list(
+		/obj/item/robot_parts,
+		/obj/item/weapon/storage/lockbox,
+		/obj/item/weapon/storage/secure,
+		/obj/item/weapon/circuitboard,
+		/obj/item/device/eftpos,
+		/obj/item/device/lightreplacer,
+		/obj/item/device/taperecorder,
+		/obj/item/device/hailer,
+		/obj/item/clothing/tie/holobadge,
+		/obj/structure/closet/crate/secure,
+		/obj/structure/closet/secure_closet,
+		/obj/machinery/librarycomp,
+		/obj/machinery/computer,
+		/obj/machinery/power,
+		/obj/machinery/suspension_gen,
+		/obj/machinery/shield_capacitor,
+		/obj/machinery/shield_gen,
+		/obj/machinery/zero_point_emitter,
+		/obj/machinery/clonepod,
+		/obj/machinery/deployable,
+		/obj/machinery/door_control,
+		/obj/machinery/porta_turret,
+		/obj/machinery/shieldgen,
+		/obj/machinery/turretid,
+		/obj/machinery/vending,
+		/obj/machinery/bot,
+		/obj/machinery/door,
+		/obj/machinery/telecomms,
+		/obj/machinery/mecha_part_fabricator
+		)
+
+
+/obj/item/weapon/card/emag/afterattack(var/obj/item/weapon/O as obj, mob/user as mob)
+
+	for(var/type in devices)
+		if(istype(O,type))
+			uses--
+			break
+
+	if(uses<1)
+		user.visible_message("[src] fizzles and sparks - it seems it's been used once too often, and is now broken.")
+		user.drop_item()
+		var/obj/item/weapon/card/emag_broken/junk = new(user.loc)
+		junk.add_fingerprint(user)
+		del(src)
+		return
+
+	..()
 
 /obj/item/weapon/card/id
 	name = "identification card"

code/modules/mob/living/carbon/human/human_defense.dm

@@ -191,6 +191,8 @@ emp_act
 			user << "\red [src]'s [affecting.display_name] is already sabotaged!"
 		else
 			user << "\red You sneakily slide [I] into the dataport on [src]'s [affecting.display_name] and short out the safeties."
+			var/obj/item/weapon/card/emag/emag = I
+			emag.uses--
 			affecting.sabotaged = 1
 		return
 

code/modules/mob/living/silicon/robot/robot.dm

@@ -697,6 +697,8 @@
 		if(!opened)//Cover is closed
 			if(locked)
 				if(prob(90))
+					var/obj/item/weapon/card/emag/emag = W
+					emag.uses--
 					user << "You emag the cover lock."
 					locked = 0
 				else

code/modules/mob/living/simple_animal/friendly/spiderbot.dm

@@ -125,6 +125,8 @@
 			user << "\red [src] is already overloaded - better run."
 			return 0
 		else
+			var/obj/item/weapon/card/emag/emag = O
+			emag.uses--
 			emagged = 1
 			user << "\blue You short out the security protocols and overload [src]'s cell, priming it to explode in a short time."
 			spawn(100)	src << "\red Your cell seems to be outputting a lot of power..."