diff --git a/code/_compile_options.dm b/code/_compile_options.dm
index 81121e19fbfba..0990e5bd29c63 100644
--- a/code/_compile_options.dm
+++ b/code/_compile_options.dm
@@ -2,7 +2,7 @@
 //#define TESTING
 
 // Uncomment the following line to compile unit tests on a local server. The output will be in a test_run-[DATE].log file in the ./data folder.
-#define LOCAL_GAME_TESTS
+// #define LOCAL_GAME_TESTS
 
 // Uncomment the following line to enable Tracy profiling.
 // DO NOT DO THIS UNLESS YOU UNDERSTAND THE IMPLICATIONS
diff --git a/code/game/objects/items/weapons/stock_parts.dm b/code/game/objects/items/weapons/stock_parts.dm
index 359802da3d5c7..4b08fc560b8d2 100644
--- a/code/game/objects/items/weapons/stock_parts.dm
+++ b/code/game/objects/items/weapons/stock_parts.dm
@@ -60,6 +60,16 @@
 		playsound(src, 'sound/machines/synth_no.ogg', 15, TRUE)
 		to_chat(user, "<span class='notice'>ERROR: [M] is out of [src]'s range!</span>")
 
+/obj/item/storage/part_replacer/tier4/populate_contents()
+	for(var/amount in 1 to 30)
+		new /obj/item/stock_parts/capacitor/quadratic(src)
+		new /obj/item/stock_parts/manipulator/femto(src)
+		new /obj/item/stock_parts/matter_bin/bluespace(src)
+		new /obj/item/stock_parts/micro_laser/quadultra(src)
+		new /obj/item/stock_parts/scanning_module/triphasic(src)
+		new /obj/item/stock_parts/cell/bluespace(src)
+		new /obj/item/reagent_containers/glass/beaker/bluespace(src)
+
 ////////////////////////////////////////
 // 		Bluespace Part Replacer
 ////////////////////////////////////////
diff --git a/code/tests/_game_test_puppeteer.dm b/code/tests/_game_test_puppeteer.dm
index bee288097247e..094525d609c70 100644
--- a/code/tests/_game_test_puppeteer.dm
+++ b/code/tests/_game_test_puppeteer.dm
@@ -50,12 +50,13 @@
 
 /datum/test_puppeteer/proc/click_on(target, params)
 	var/datum/test_puppeteer/puppet_target = target
-	sleep(max(puppet.next_click, puppet.next_move) - world.time + 1)
 	if(istype(puppet_target))
 		puppet.ClickOn(puppet_target.puppet, params)
 		return
 
 	puppet.ClickOn(target, params)
+	puppet.next_click = world.time
+	puppet.next_move = world.time
 
 /datum/test_puppeteer/proc/spawn_mob_nearby(mob_type)
 	for(var/turf/T in RANGE_TURFS(1, puppet))
@@ -105,3 +106,25 @@
 		for(var/atom/A in T.contents)
 			if(istype(A, atom_type))
 				return A
+
+// No we don't technically need to put these things into an actual backpack and
+// so forth, we could just leave them lying around and teleport them to the
+// player but this keeps things realistic and may surface issues we wouldn't
+// think to test for.
+/datum/test_puppeteer/proc/put_away(obj/object)
+	if(!puppet.back)
+		puppet.equip_to_appropriate_slot(new/obj/item/storage/backpack)
+
+	var/obj/item/storage/backpack = puppet.back
+	backpack.handle_item_insertion(object, puppet)
+
+/datum/test_puppeteer/proc/retrieve(obj/object)
+	if(!puppet.back)
+		return
+
+	var/obj/item/storage/backpack = puppet.back
+	if(!(object in backpack.contents))
+		return
+
+	backpack.remove_item_from_storage(object)
+	puppet.put_in_active_hand(object)
diff --git a/code/tests/attack_chain/test_attack_chain_machinery.dm b/code/tests/attack_chain/test_attack_chain_machinery.dm
index 048bd10829957..6fdd8dd83cbe2 100644
--- a/code/tests/attack_chain/test_attack_chain_machinery.dm
+++ b/code/tests/attack_chain/test_attack_chain_machinery.dm
@@ -31,7 +31,7 @@
 	var/obj/screwdriver = player.spawn_obj_in_hand(/obj/item/screwdriver)
 	player.click_on(scanner)
 	TEST_ASSERT_LAST_CHATLOG(player, "You open the maintenance hatch")
-	qdel(screwdriver)
+	player.put_away(screwdriver)
 
 	// Abductor console
 	var/obj/abductor_console = teleport_to_first(player, /obj/machinery/abductor/console)
@@ -43,34 +43,66 @@
 	player.set_intent("harm")
 	player.click_on(abductor_console)
 	TEST_ASSERT_LAST_CHATLOG(player, "You hit Abductor console with the welding tool!")
-	qdel(welder)
+	player.set_intent("help")
+	player.put_away(welder)
 
+	// Abductor replacement organ storage
 	var/obj/machinery/abductor/gland_dispenser/dispenser = teleport_to_first(player, /obj/machinery/abductor/gland_dispenser)
 	var/obj/gland = player.spawn_obj_in_hand(/obj/item/organ/internal/heart/gland)
 	player.click_on(dispenser)
 	TEST_ASSERT(gland in dispenser.contents, "did not place gland in dispenser")
 
+	// Autolathe
 	var/obj/autolathe = teleport_to_first(player, /obj/machinery/autolathe)
 	var/obj/design_disk = player.spawn_obj_in_hand(/obj/item/disk/design_disk/golem_shell)
 	player.click_on(autolathe)
 	TEST_ASSERT_LAST_CHATLOG(player, "You begin to load a design")
 	qdel(design_disk)
+	player.retrieve(screwdriver)
+	player.click_on(autolathe)
+	TEST_ASSERT_LAST_CHATLOG(player, "You open the maintenance hatch")
+	player.put_away(screwdriver)
+	player.spawn_obj_in_hand(/obj/item/storage/part_replacer/tier4)
+	player.click_on(autolathe)
+	TEST_ASSERT_LAST_CHATLOG(player, "micro-manipulator replaced with femto-manipulator")
 
-	var/obj/nuke = teleport_to_first(player, /obj/machinery/nuclearbomb/undeployed)
-	var/obj/disk = player.spawn_obj_in_hand(/obj/item/disk/nuclear)
+	var/obj/machinery/nuclearbomb/nuke = teleport_to_first(player, /obj/machinery/nuclearbomb/undeployed)
+	var/obj/disk = player.spawn_obj_in_hand(/obj/item/disk/nuclear/unrestricted)
 	player.click_on(nuke)
 	TEST_ASSERT_LAST_CHATLOG(player, "You need to deploy")
-	nuke.ui_act("deploy")
+	nuke.extended = TRUE
 	player.click_on(nuke)
 	TEST_ASSERT(disk in nuke.contents, "Disk not inserted into nuke")
-	screwdriver = player.spawn_obj_in_hand(/obj/item/screwdriver)
+	player.retrieve(screwdriver)
 	player.click_on(nuke)
 	TEST_ASSERT_LAST_CHATLOG(player, "You unscrew the control panel")
+	player.put_away(screwdriver)
 
 	var/obj/camera = teleport_to_first(player, /obj/machinery/camera)
+	player.retrieve(screwdriver)
 	player.click_on(camera) // with screwdriver
 	TEST_ASSERT_LAST_CHATLOG(player, "panel open")
-	qdel(screwdriver)
+	player.put_away(screwdriver)
 	player.spawn_obj_in_hand(/obj/item/stack/sheet/mineral/plasma)
 	player.click_on(camera)
-	TEST_ASSERT_LAST_CHATLOG(player, "You attach the stack of plasma")
+	TEST_ASSERT_LAST_CHATLOG(player, "You attach the solid plasma")
+	var/obj/knife = player.spawn_obj_in_hand(/obj/item/kitchen/knife)
+	player.set_intent("harm")
+	player.click_on(camera)
+	TEST_ASSERT_LAST_CHATLOG(player, "You hit the security camera with the kitchen knife")
+	player.set_intent("help")
+	qdel(knife)
+
+	var/obj/chem_dispenser = teleport_to_first(player, /obj/machinery/chem_dispenser)
+	player.retrieve(screwdriver)
+	player.click_on(chem_dispenser)
+	TEST_ASSERT_LAST_CHATLOG(player, "You open the maintenance hatch")
+	player.puppet.swap_hand()
+	player.spawn_obj_in_hand(/obj/item/reagent_containers/glass/beaker)
+	player.click_on(chem_dispenser)
+	TEST_ASSERT_LAST_CHATLOG(player, "Close the maintenance panel first")
+	player.puppet.swap_hand()
+	player.click_on(chem_dispenser)
+	player.puppet.swap_hand()
+	player.click_on(chem_dispenser)
+	TEST_ASSERT_LAST_CHATLOG(player, "You set the beaker on the machine")