diff --git a/code/game/objects/items/cards_ids.dm b/code/game/objects/items/cards_ids.dm
index 805592f6887..b30f1420596 100644
--- a/code/game/objects/items/cards_ids.dm
+++ b/code/game/objects/items/cards_ids.dm
@@ -45,8 +45,8 @@
 	name = "retro identification card"
 	desc = "A card used to provide ID and determine access across the station."
 	icon_state = "card_grey"
-	worn_icon_state = "card_retro"
 	inhand_icon_state = "card-id"
+	worn_icon_state = "nothing"
 	lefthand_file = 'icons/mob/inhands/equipment/idcards_lefthand.dmi'
 	righthand_file = 'icons/mob/inhands/equipment/idcards_righthand.dmi'
 	slot_flags = ITEM_SLOT_ID
@@ -880,7 +880,6 @@
 	name = "identification card"
 	desc = "A card used to provide ID and determine access across the station. Has an integrated digital display and advanced microchips."
 	icon_state = "card_grey"
-	worn_icon_state = "card_grey"
 
 	wildcard_slots = WILDCARD_LIMIT_GREY
 	flags_1 = UNPAINTABLE_1
@@ -1038,13 +1037,11 @@
 	name = "rainbow identification card"
 	desc = "A rainbow card, promoting fun in a 'business proper' sense!"
 	icon_state = "card_rainbow"
-	worn_icon_state = "card_rainbow"
 
 /obj/item/card/id/advanced/silver
 	name = "silver identification card"
 	desc = "A silver card which shows honour and dedication."
 	icon_state = "card_silver"
-	worn_icon_state = "card_silver"
 	inhand_icon_state = "silver_id"
 	assigned_icon_state = "assigned_silver"
 	wildcard_slots = WILDCARD_LIMIT_SILVER
@@ -1063,7 +1060,6 @@
 	name = "gold identification card"
 	desc = "A golden card which shows power and might."
 	icon_state = "card_gold"
-	worn_icon_state = "card_gold"
 	inhand_icon_state = "gold_id"
 	assigned_icon_state = "assigned_gold"
 	wildcard_slots = WILDCARD_LIMIT_GOLD
@@ -1090,7 +1086,6 @@
 	name = "\improper CentCom ID"
 	desc = "An ID straight from Central Command."
 	icon_state = "card_centcom"
-	worn_icon_state = "card_centcom"
 	assigned_icon_state = "assigned_centcom"
 	registered_name = JOB_CENTCOM
 	registered_age = null
@@ -1136,7 +1131,6 @@
 	name = "black identification card"
 	desc = "This card is telling you one thing and one thing alone. The person holding this card is an utter badass."
 	icon_state = "card_black"
-	worn_icon_state = "card_black"
 	assigned_icon_state = "assigned_syndicate"
 	wildcard_slots = WILDCARD_LIMIT_GOLD
 
@@ -1186,7 +1180,6 @@
 	name = "\improper Debug ID"
 	desc = "A debug ID card. Has ALL the all access, you really shouldn't have this."
 	icon_state = "card_centcom"
-	worn_icon_state = "card_centcom"
 	assigned_icon_state = "assigned_centcom"
 	trim = /datum/id_trim/admin
 	wildcard_slots = WILDCARD_LIMIT_ADMIN
@@ -1199,7 +1192,6 @@
 	name = "prisoner ID card"
 	desc = "You are a number, you are not a free man."
 	icon_state = "card_prisoner"
-	worn_icon_state = "card_prisoner"
 	inhand_icon_state = "orange-id"
 	lefthand_file = 'icons/mob/inhands/equipment/idcards_lefthand.dmi'
 	righthand_file = 'icons/mob/inhands/equipment/idcards_righthand.dmi'
@@ -1312,7 +1304,6 @@
 	registered_name = "Highlander"
 	desc = "There can be only one!"
 	icon_state = "card_black"
-	worn_icon_state = "card_black"
 	assigned_icon_state = "assigned_syndicate"
 	trim = /datum/id_trim/highlander
 	wildcard_slots = WILDCARD_LIMIT_ADMIN
@@ -1605,7 +1596,6 @@
 /// A special variant of the classic chameleon ID card which accepts all access.
 /obj/item/card/id/advanced/chameleon/black
 	icon_state = "card_black"
-	worn_icon_state = "card_black"
 	assigned_icon_state = "assigned_syndicate"
 	wildcard_slots = WILDCARD_LIMIT_GOLD
 
diff --git a/code/game/objects/items/devices/scanners/gas_analyzer.dm b/code/game/objects/items/devices/scanners/gas_analyzer.dm
index 95f321e7171..0e55a8f7087 100644
--- a/code/game/objects/items/devices/scanners/gas_analyzer.dm
+++ b/code/game/objects/items/devices/scanners/gas_analyzer.dm
@@ -204,6 +204,7 @@
 	desc = "A hand-held long-range environmental scanner which reports current gas levels."
 	name = "long-range gas analyzer"
 	icon_state = "analyzerranged"
+	worn_icon_state = "analyzer"
 	w_class = WEIGHT_CLASS_NORMAL
 	custom_materials = list(/datum/material/iron = 100, /datum/material/glass = 20, /datum/material/gold = 300, /datum/material/bluespace=200)
 	grind_results = list(/datum/reagent/mercury = 5, /datum/reagent/iron = 5, /datum/reagent/silicon = 5)
diff --git a/code/game/objects/items/emags.dm b/code/game/objects/items/emags.dm
index 89df0b9db49..49bbc14f8d6 100644
--- a/code/game/objects/items/emags.dm
+++ b/code/game/objects/items/emags.dm
@@ -135,7 +135,7 @@
 	desc = "An ominous card that contains the location of the station, and when applied to a communications console, \
 	the ability to long-distance contact the Syndicate fleet."
 	icon_state = "battlecruisercaller"
-	worn_icon_state = "battlecruisercaller"
+	worn_icon_state = "emag"
 	///whether we have called the battlecruiser
 	var/used = FALSE
 	/// The battlecruiser team that the battlecruiser will get added to
diff --git a/code/game/objects/items/religion.dm b/code/game/objects/items/religion.dm
index 23d8ee44831..9b143fa5728 100644
--- a/code/game/objects/items/religion.dm
+++ b/code/game/objects/items/religion.dm
@@ -272,6 +272,7 @@
 	name = "Crusader's Hood"
 	desc = "A brownish hood."
 	icon = 'icons/obj/clothing/head/chaplain.dmi'
+	worn_icon = 'icons/mob/clothing/head/chaplain.dmi'
 	icon_state = "crusader"
 	inhand_icon_state = null
 	w_class = WEIGHT_CLASS_NORMAL
@@ -300,6 +301,7 @@
 	name = "Prophet's Hat"
 	desc = "A religious-looking hat."
 	icon_state = null
+	worn_icon = 'icons/mob/clothing/head/helmet.dmi'
 	inhand_icon_state = null
 	flags_1 = 0
 	armor_type = /datum/armor/crusader_prophet
diff --git a/code/game/objects/items/storage/wallets.dm b/code/game/objects/items/storage/wallets.dm
index 413b319eb09..13f321b5106 100644
--- a/code/game/objects/items/storage/wallets.dm
+++ b/code/game/objects/items/storage/wallets.dm
@@ -151,6 +151,7 @@
 
 /obj/item/storage/wallet/random
 	icon_state = "random_wallet" // for mapping purposes
+	worn_icon_state = "wallet"
 
 /obj/item/storage/wallet/random/Initialize(mapload)
 	. = ..()
diff --git a/code/game/objects/structures/bedsheet_bin.dm b/code/game/objects/structures/bedsheet_bin.dm
index 71eb2819196..ce83258a28a 100644
--- a/code/game/objects/structures/bedsheet_bin.dm
+++ b/code/game/objects/structures/bedsheet_bin.dm
@@ -338,6 +338,7 @@ LINEN BINS
 	name = "random bedsheet"
 	desc = "If you're reading this description ingame, something has gone wrong! Honk!"
 	bedsheet_type = BEDSHEET_ABSTRACT
+	item_flags = ABSTRACT
 	var/static/list/bedsheet_list
 	var/spawn_type = BEDSHEET_SINGLE
 
@@ -364,6 +365,7 @@ LINEN BINS
 	name = "random dorms bedsheet"
 	desc = "If you're reading this description ingame, something has gone wrong! Honk!"
 	bedsheet_type = BEDSHEET_DOUBLE
+	item_flags = ABSTRACT
 	slot_flags = null
 
 /obj/item/bedsheet/dorms/Initialize(mapload)
@@ -545,6 +547,7 @@ LINEN BINS
 
 /obj/item/bedsheet/dorms_double
 	icon_state = "random_bedsheet"
+	item_flags = ABSTRACT
 	bedsheet_type = BEDSHEET_ABSTRACT
 
 /obj/item/bedsheet/dorms_double/Initialize(mapload)
diff --git a/code/modules/antagonists/changeling/powers/mutations.dm b/code/modules/antagonists/changeling/powers/mutations.dm
index 4560c986a37..01930613fd9 100644
--- a/code/modules/antagonists/changeling/powers/mutations.dm
+++ b/code/modules/antagonists/changeling/powers/mutations.dm
@@ -476,6 +476,7 @@
 	name = "flesh mass"
 	icon_state = "lingspacesuit_t"
 	icon = 'icons/obj/clothing/suits/costume.dmi'
+	worn_icon = 'icons/mob/clothing/suits/costume.dmi'
 	desc = "A huge, bulky mass of pressure and temperature-resistant organic tissue, evolved to facilitate space travel."
 	item_flags = DROPDEL
 	clothing_flags = STOPSPRESSUREDAMAGE //Not THICKMATERIAL because it's organic tissue, so if somebody tries to inject something into it, it still ends up in your blood. (also balance but muh fluff)
diff --git a/code/modules/hydroponics/grown/rainbow_bunch.dm b/code/modules/hydroponics/grown/rainbow_bunch.dm
index 91c6aae2cfa..14d0648b666 100644
--- a/code/modules/hydroponics/grown/rainbow_bunch.dm
+++ b/code/modules/hydroponics/grown/rainbow_bunch.dm
@@ -33,12 +33,13 @@
 	throw_range = 3
 	attack_verb_continuous = list("pompfs")
 	attack_verb_simple = list("pompf")
+	greyscale_colors = "#000000" //only here for unit testing. overriden in initialize()
 	greyscale_config = /datum/greyscale_config/flower_simple
 	greyscale_config_worn = /datum/greyscale_config/flower_simple_worn
 
 /obj/item/food/grown/rainbow_flower/Initialize(mapload)
 	. = ..()
-	if(greyscale_colors)
+	if(greyscale_colors != initial(greyscale_colors))
 		return
 
 	var/flower_color = rand(1,8)
diff --git a/code/modules/instruments/piano_synth.dm b/code/modules/instruments/piano_synth.dm
index 630bf8819dd..416d164cac0 100644
--- a/code/modules/instruments/piano_synth.dm
+++ b/code/modules/instruments/piano_synth.dm
@@ -56,6 +56,7 @@
 	name = "\improper Nanotrasen space pods"
 	desc = "Flex your money, AND ignore what everyone else says, all at once!"
 	icon_state = "spacepods"
+	worn_icon = 'icons/mob/clothing/ears.dmi'
 	inhand_icon_state = null
 	slot_flags = ITEM_SLOT_EARS
 	strip_delay = 100 //air pods don't fall out
diff --git a/code/modules/mob/living/carbon/human/human_update_icons.dm b/code/modules/mob/living/carbon/human/human_update_icons.dm
index 50929e504e5..aa92c242850 100644
--- a/code/modules/mob/living/carbon/human/human_update_icons.dm
+++ b/code/modules/mob/living/carbon/human/human_update_icons.dm
@@ -147,7 +147,7 @@ There are several things that need to be remembered:
 		var/icon_file
 
 		if(!icon_exists(icon_file, RESOLVE_ICON_STATE(worn_item)))
-			icon_file = 'icons/mob/simple/mob.dmi'
+			icon_file = 'icons/mob/clothing/id.dmi'
 
 		id_overlay = wear_id.build_worn_icon(default_layer = ID_LAYER, default_icon_file = icon_file)
 
diff --git a/code/modules/recycling/sortingmachinery.dm b/code/modules/recycling/sortingmachinery.dm
index 9f0a25b8886..2e48818bb10 100644
--- a/code/modules/recycling/sortingmachinery.dm
+++ b/code/modules/recycling/sortingmachinery.dm
@@ -260,7 +260,7 @@
 	desc = "Used to set the destination of properly wrapped packages."
 	icon = 'icons/obj/device.dmi'
 	icon_state = "cargo tagger"
-	worn_icon_state = "cargo tagger"
+	worn_icon_state = "cargotagger"
 	var/currTag = 0 //Destinations are stored in code\globalvars\lists\flavor_misc.dm
 	var/locked_destination = FALSE //if true, users can't open the destination tag window to prevent changing the tagger's current destination
 	w_class = WEIGHT_CLASS_TINY
diff --git a/code/modules/unit_tests/_unit_tests.dm b/code/modules/unit_tests/_unit_tests.dm
index 2b934bf479e..59a4e947550 100644
--- a/code/modules/unit_tests/_unit_tests.dm
+++ b/code/modules/unit_tests/_unit_tests.dm
@@ -208,6 +208,7 @@
 #include "verify_config_tags.dm"
 #include "verify_emoji_names.dm"
 #include "wizard_loadout.dm"
+#include "worn_icons.dm"
 #ifdef REFERENCE_TRACKING_DEBUG //Don't try and parse this file if ref tracking isn't turned on. IE: don't parse ref tracking please mr linter
 #include "find_reference_sanity.dm"
 #endif
diff --git a/code/modules/unit_tests/screenshots/screenshot_humanoids__datum_species_golem_cardboard.png b/code/modules/unit_tests/screenshots/screenshot_humanoids__datum_species_golem_cardboard.png
index 4d5f458fd9f..ba4d67ad07f 100644
Binary files a/code/modules/unit_tests/screenshots/screenshot_humanoids__datum_species_golem_cardboard.png and b/code/modules/unit_tests/screenshots/screenshot_humanoids__datum_species_golem_cardboard.png differ
diff --git a/code/modules/unit_tests/worn_icons.dm b/code/modules/unit_tests/worn_icons.dm
new file mode 100644
index 00000000000..ce1b0540249
--- /dev/null
+++ b/code/modules/unit_tests/worn_icons.dm
@@ -0,0 +1,117 @@
+/// Makes sure suit slot items aren't using CS:S fallbacks.
+/datum/unit_test/worn_icons
+	var/static/list/possible_icon_states = list()
+	/// additional_icon_location is for downstream modularity support for finding missing sprites in additonal DMI file locations.
+	/// Make sure this location is also present in tools/deploy.sh
+	/// If you need additional paths ontop of this second one, you can add another generate_possible_icon_states_list("your/folder/path/") below the if(additional_icon_location) block in Run(), and make sure to add that path to tools/deploy.sh as well.
+	var/additional_icon_location = null
+
+/datum/unit_test/worn_icons/proc/generate_possible_icon_states_list(directory_path)
+	if(!directory_path)
+		directory_path = "icons/mob/clothing/"
+	for(var/file_path in flist(directory_path))
+		if(findtext(file_path, ".dmi"))
+			for(var/sprite_icon in icon_states("[directory_path][file_path]", 1)) //2nd arg = 1 enables 64x64+ icon support, otherwise you'll end up with "sword0_1" instead of "sword"
+				possible_icon_states[sprite_icon] += list("[directory_path][file_path]")
+		else
+			possible_icon_states += generate_possible_icon_states_list("[directory_path][file_path]")
+
+/datum/unit_test/worn_icons/Run()
+	generate_possible_icon_states_list()
+	if(additional_icon_location)
+		generate_possible_icon_states_list(additional_icon_location)
+
+	var/list/already_warned_icons = list()
+
+	for(var/obj/item/item_path as anything in (subtypesof(/obj/item) - typesof(/obj/item/mod)))
+		var/cached_slot_flags = initial(item_path.slot_flags)
+		if(!cached_slot_flags || (cached_slot_flags & ITEM_SLOT_LPOCKET) || (cached_slot_flags & ITEM_SLOT_RPOCKET) || initial(item_path.item_flags) & ABSTRACT)
+			continue
+
+
+		if(initial(item_path.greyscale_colors) && initial(item_path.greyscale_config)) //GAGS has its own unit test.
+			continue
+
+		var/worn_icon = initial(item_path.worn_icon) //override icon file. where our sprite is contained if set. (ie modularity stuff)
+		var/worn_icon_state = initial(item_path.worn_icon_state) //overrides icon_state.
+		var/icon_state = worn_icon_state || initial(item_path.icon_state) //icon_state. what sprite name we are looking for.
+
+
+		if(isnull(icon_state))
+			continue //no sprite for the item.
+		if(icon_state in already_warned_icons)
+			continue
+
+		var/match_message
+		if(icon_state in possible_icon_states)
+			for(var/file_place in possible_icon_states[icon_state])
+				match_message += (match_message ? " & '[file_place]'" : " - Matching sprite found in: '[file_place]'")
+
+		if(worn_icon) //easiest to check since we override everything. this automatically includes downstream support.
+			if(!(icon_state in icon_states(worn_icon, 1)))
+				TEST_FAIL("[item_path] using invalid [worn_icon_state ? "worn_icon_state" : "icon_state"], \"[icon_state]\" in worn_icon override file, '[worn_icon]'[match_message]")
+			continue
+
+		var/icon_file //checks against all the default icon locations if one isn't defined.
+		var/fail_reasons
+		var/spacer
+		if(cached_slot_flags & ITEM_SLOT_BACK)
+			icon_file = 'icons/mob/clothing/back.dmi'
+
+			if(!(icon_state in icon_states(icon_file, 1)))
+				already_warned_icons += icon_state
+				fail_reasons += "[item_path] using invalid [worn_icon_state ? "worn_icon_state" : "icon_state"], \"[icon_state]\" in '[icon_file]'[match_message]"
+				spacer = "\n\t"
+
+		if(cached_slot_flags & ITEM_SLOT_ID)
+			icon_file = 'icons/mob/clothing/id.dmi'
+			if(!(icon_state in icon_states(icon_file, 1)))
+				already_warned_icons += icon_state
+				fail_reasons += "[spacer][item_path] using invalid [worn_icon_state ? "worn_icon_state" : "icon_state"], \"[icon_state]\" in '[icon_file]'[match_message]"
+				spacer = "\n\t"
+
+		if(cached_slot_flags & ITEM_SLOT_GLOVES)
+			icon_file = 'icons/mob/clothing/hands.dmi'
+			if(!(icon_state in icon_states(icon_file, 1)))
+				already_warned_icons += icon_state
+				fail_reasons += "[spacer][item_path] using invalid [worn_icon_state ? "worn_icon_state" : "icon_state"], \"[icon_state]\" in '[icon_file]'[match_message]"
+				spacer = "\n\t"
+
+		if(cached_slot_flags & ITEM_SLOT_EYES)
+			icon_file = 'icons/mob/clothing/eyes.dmi'
+			if(!(icon_state in icon_states(icon_file, 1)))
+				already_warned_icons += icon_state
+				fail_reasons += "[spacer][item_path] using invalid [worn_icon_state ? "worn_icon_state" : "icon_state"], \"[icon_state]\" in '[icon_file]'[match_message]"
+				spacer = "\n\t"
+
+		if(cached_slot_flags & ITEM_SLOT_EARS)
+			icon_file = 'icons/mob/clothing/ears.dmi'
+			if(!(icon_state in icon_states(icon_file, 1)))
+				already_warned_icons += icon_state
+				fail_reasons += "[spacer][item_path] using invalid [worn_icon_state ? "worn_icon_state" : "icon_state"], \"[icon_state]\" in '[icon_file]'[match_message]"
+				spacer = "\n\t"
+
+		if(cached_slot_flags & ITEM_SLOT_NECK)
+			icon_file = 'icons/mob/clothing/neck.dmi'
+			if(!(icon_state in icon_states(icon_file, 1)))
+				already_warned_icons += icon_state
+				fail_reasons += "[spacer][item_path] using invalid [worn_icon_state ? "worn_icon_state" : "icon_state"], \"[icon_state]\" in '[icon_file]'[match_message]"
+				spacer = "\n\t"
+
+		if(cached_slot_flags & ITEM_SLOT_MASK)
+			icon_file = 'icons/mob/clothing/mask.dmi'
+			if(!(icon_state in icon_states(icon_file, 1)))
+				already_warned_icons += icon_state
+				fail_reasons += "[spacer][item_path] using invalid [worn_icon_state ? "worn_icon_state" : "icon_state"], \"[icon_state]\" in '[icon_file]'[match_message]"
+				spacer = "\n\t"
+
+		if(cached_slot_flags & ITEM_SLOT_BELT)
+			icon_file = 'icons/mob/clothing/belt.dmi'
+			if(!(icon_state in icon_states(icon_file, 1)))
+				already_warned_icons += icon_state
+				fail_reasons += "[spacer][item_path] using invalid [worn_icon_state ? "worn_icon_state" : "icon_state"], \"[icon_state]\" in '[icon_file]'[match_message]"
+				spacer = "\n\t"
+
+		if(fail_reasons)
+			TEST_FAIL(fail_reasons)
+
diff --git a/icons/mob/clothing/back.dmi b/icons/mob/clothing/back.dmi
index 21d49fc738c..1de907be97c 100644
Binary files a/icons/mob/clothing/back.dmi and b/icons/mob/clothing/back.dmi differ
diff --git a/icons/mob/clothing/belt.dmi b/icons/mob/clothing/belt.dmi
index 6c0e5014909..3bb1c17e35d 100644
Binary files a/icons/mob/clothing/belt.dmi and b/icons/mob/clothing/belt.dmi differ
diff --git a/icons/mob/clothing/id.dmi b/icons/mob/clothing/id.dmi
index 1b3f320c753..d5ed308f5d9 100644
Binary files a/icons/mob/clothing/id.dmi and b/icons/mob/clothing/id.dmi differ
diff --git a/icons/mob/clothing/id_card.dmi b/icons/mob/clothing/id_card.dmi
deleted file mode 100644
index ab573279f30..00000000000
Binary files a/icons/mob/clothing/id_card.dmi and /dev/null differ
diff --git a/tools/deploy.sh b/tools/deploy.sh
index 8a0cf9d29a3..b91eee1331e 100755
--- a/tools/deploy.sh
+++ b/tools/deploy.sh
@@ -11,9 +11,10 @@ fi
 
 mkdir -p \
     $1/_maps \
-	$1/icons/effects \
-	$1/icons/mob/clothing \
+    $1/icons/effects \
+    $1/icons/mob/clothing \
     $1/icons/mob/inhands \
+    $1/icons/mob/simple \
     $1/icons/obj \
     $1/icons/runtime \
     $1/sound/runtime \
@@ -31,6 +32,7 @@ cp -r _maps/* $1/_maps/
 cp -r icons/effects/* $1/icons/effects/
 cp -r icons/mob/clothing/* $1/icons/mob/clothing/
 cp -r icons/mob/inhands/* $1/icons/mob/inhands/
+cp -r icons/mob/simple/* $1/icons/mob/simple/
 cp -r icons/obj/* $1/icons/obj/
 cp -r icons/runtime/* $1/icons/runtime/
 cp -r sound/runtime/* $1/sound/runtime/