diff --git a/SpacemanDMM.toml b/SpacemanDMM.toml
index ec6f5ef068f..af773c3ab00 100644
--- a/SpacemanDMM.toml
+++ b/SpacemanDMM.toml
@@ -36,3 +36,6 @@ hide_invisible = [
 smart-cables = false
 # With the multitile component and the removal of the gravity gen parts, the gravity generator will fail the render passes
 gravity-gen = false
+
+[diagnostics]
+redefined_proc = "error"
diff --git a/code/__DEFINES/_spacemandmm.dm b/__spacemandmm.dm
similarity index 91%
rename from code/__DEFINES/_spacemandmm.dm
rename to __spacemandmm.dm
index 8112a60eaec..237146b7bf3 100644
--- a/code/__DEFINES/_spacemandmm.dm
+++ b/__spacemandmm.dm
@@ -12,6 +12,8 @@
 	#define PRIVATE_PROC(X) set SpacemanDMM_private_proc = X
 	/// Protected procs can only be call by things of the same type or subtypes
 	#define PROTECTED_PROC(X) set SpacemanDMM_protected_proc = X
+	/// Redefinable procs permit multiple declarations of themselves.
+	#define CAN_BE_REDEFINED(X) set SpacemanDMM_can_be_redefined = X
 	/// Final vars forbid overriding their value by types that inherit it.
 	#define VAR_FINAL var/SpacemanDMM_final
 	/// Private vars can only be called by things of exactly the same type
@@ -27,6 +29,7 @@
 	#define SHOULD_BE_PURE(X)
 	#define PRIVATE_PROC(X)
 	#define PROTECTED_PROC(X)
+	#define CAN_BE_REDEFINED(X)
 	#define VAR_FINAL var
 	#define VAR_PRIVATE var
 	#define VAR_PROTECTED var
diff --git a/code/__DEFINES/MC.dm b/code/__DEFINES/MC.dm
index 641fcc941d3..828192403d9 100644
--- a/code/__DEFINES/MC.dm
+++ b/code/__DEFINES/MC.dm
@@ -93,7 +93,7 @@
 	PreInit();\
 	ss_id="timer_[#X]";\
 }\
-/datum/controller/subsystem/timer/##X/fire() {..() /*just so it shows up on the profiler*/} \
+/datum/controller/subsystem/timer/##X/fire() {CAN_BE_REDEFINED(TRUE); ..() } \
 /datum/controller/subsystem/timer/##X
 
 #define MOVEMENT_SUBSYSTEM_DEF(X) GLOBAL_REAL(SS##X, /datum/controller/subsystem/movement/##X);\
diff --git a/code/__DEFINES/_globals.dm b/code/__DEFINES/_globals.dm
index f8066168814..ec7015a81af 100644
--- a/code/__DEFINES/_globals.dm
+++ b/code/__DEFINES/_globals.dm
@@ -4,11 +4,12 @@
 	##X = ##InitValue;\
 	gvars_datum_init_order += #X;\
 }
-#define GLOBAL_UNMANAGED(X) /datum/controller/global_vars/proc/InitGlobal##X() { return; }
+#define GLOBAL_UNMANAGED(X) /datum/controller/global_vars/proc/InitGlobal##X() { CAN_BE_REDEFINED(TRUE); return; }
 
 #ifndef TESTING
 #define GLOBAL_PROTECT(X)\
 /datum/controller/global_vars/InitGlobal##X(){\
+	CAN_BE_REDEFINED(TRUE);\
 	..();\
 	gvars_datum_protected_varlist[#X] = TRUE;\
 }
diff --git a/code/__DEFINES/tgs.dm b/code/__DEFINES/tgs.dm
index 2b233bca7d2..f66596e87d8 100644
--- a/code/__DEFINES/tgs.dm
+++ b/code/__DEFINES/tgs.dm
@@ -151,6 +151,7 @@
  * * minimum_required_security_level: The minimum required security level to run the game in which the DMAPI is integrated. Can be one of [TGS_SECURITY_ULTRASAFE], [TGS_SECURITY_SAFE], or [TGS_SECURITY_TRUSTED].
  */
 /world/proc/TgsNew(datum/tgs_event_handler/event_handler, minimum_required_security_level = TGS_SECURITY_ULTRASAFE)
+	CAN_BE_REDEFINED(TRUE)
 	return
 
 /**
@@ -161,6 +162,7 @@
  * This function should not be called before ..() in [/world/proc/New].
  */
 /world/proc/TgsInitializationComplete()
+	CAN_BE_REDEFINED(TRUE)
 	return
 
 /// Put this at the start of [/world/proc/Topic].
@@ -170,6 +172,7 @@
  * Call this as late as possible in [world/proc/Reboot] (BEFORE ..()).
  */
 /world/proc/TgsReboot()
+	CAN_BE_REDEFINED(TRUE)
 	return
 
 // DATUM DEFINITIONS
@@ -207,6 +210,7 @@
  * Returns [TRUE]/[FALSE] based on if the [/datum/tgs_version] contains wildcards.
  */
 /datum/tgs_version/proc/Wildcard()
+	CAN_BE_REDEFINED(TRUE)
 	return
 
 /**
@@ -215,6 +219,7 @@
  * other_version - The [/datum/tgs_version] to compare against.
  */
 /datum/tgs_version/proc/Equals(datum/tgs_version/other_version)
+	CAN_BE_REDEFINED(TRUE)
 	return
 
 /// Represents a merge of a GitHub pull request.
@@ -401,16 +406,19 @@
 
 /// Returns the maximum supported [/datum/tgs_version] of the DMAPI.
 /world/proc/TgsMaximumApiVersion()
+	CAN_BE_REDEFINED(TRUE)
 	return
 
 /// Returns the minimum supported [/datum/tgs_version] of the DMAPI.
 /world/proc/TgsMinimumApiVersion()
+	CAN_BE_REDEFINED(TRUE)
 	return
 
 /**
  * Returns [TRUE] if DreamDaemon was launched under TGS, the API matches, and was properly initialized. [FALSE] will be returned otherwise.
  */
 /world/proc/TgsAvailable()
+	CAN_BE_REDEFINED(TRUE)
 	return
 
 // No function below this succeeds if it TgsAvailable() returns FALSE or if TgsNew() has yet to be called.
@@ -422,6 +430,7 @@
  * If TGS has not requested a [TGS_REBOOT_MODE_SHUTDOWN] DreamDaemon will be launched again.
  */
 /world/proc/TgsEndProcess()
+	CAN_BE_REDEFINED(TRUE)
 	return
 
 /**
@@ -431,6 +440,7 @@
  * admin_only: If [TRUE], message will be sent to admin connected chats. Vice-versa applies.
  */
 /world/proc/TgsTargetedChatBroadcast(datum/tgs_message_content/message, admin_only = FALSE)
+	CAN_BE_REDEFINED(TRUE)
 	return
 
 /**
@@ -440,6 +450,7 @@
  * user: The [/datum/tgs_chat_user] to PM.
  */
 /world/proc/TgsChatPrivateMessage(datum/tgs_message_content/message, datum/tgs_chat_user/user)
+	CAN_BE_REDEFINED(TRUE)
 	return
 
 /**
@@ -449,42 +460,52 @@
  * channels - Optional list of [/datum/tgs_chat_channel]s to restrict the message to.
  */
 /world/proc/TgsChatBroadcast(datum/tgs_message_content/message, list/channels = null)
+	CAN_BE_REDEFINED(TRUE)
 	return
 
 /// Returns the current [/datum/tgs_version] of TGS if it is running the server, null otherwise. This function may sleep if the call to [/world/proc/TgsNew] is sleeping!
 /world/proc/TgsVersion()
+	CAN_BE_REDEFINED(TRUE)
 	return
 
 /// Returns the running engine type
 /world/proc/TgsEngine()
+	CAN_BE_REDEFINED(TRUE)
 	return
 
 /// Returns the current [/datum/tgs_version] of the DMAPI being used if it was activated, null otherwise. This function may sleep if the call to [/world/proc/TgsNew] is sleeping!
 /world/proc/TgsApiVersion()
+	CAN_BE_REDEFINED(TRUE)
 	return
 
 /// Returns the name of the TGS instance running the game if TGS is present, null otherwise. This function may sleep if the call to [/world/proc/TgsNew] is sleeping!
 /world/proc/TgsInstanceName()
+	CAN_BE_REDEFINED(TRUE)
 	return
 
 /// Return the current [/datum/tgs_revision_information] of the running server if TGS is present, null otherwise. This function may sleep if the call to [/world/proc/TgsNew] is sleeping!
 /world/proc/TgsRevision()
+	CAN_BE_REDEFINED(TRUE)
 	return
 
 /// Returns the current BYOND security level as a TGS_SECURITY_ define if TGS is present, null otherwise. This function may sleep if the call to [/world/proc/TgsNew] is sleeping!
 /world/proc/TgsSecurityLevel()
+	CAN_BE_REDEFINED(TRUE)
 	return
 
 /// Returns the current BYOND visibility level as a TGS_VISIBILITY_ define if TGS is present, null otherwise. Requires TGS to be using interop API version 5 or higher otherwise the string "___unimplemented" wil be returned. This function may sleep if the call to [/world/proc/TgsNew] is sleeping!
 /world/proc/TgsVisibility()
+	CAN_BE_REDEFINED(TRUE)
 	return
 
 /// Returns a list of active [/datum/tgs_revision_information/test_merge]s if TGS is present, null otherwise. This function may sleep if the call to [/world/proc/TgsNew] is sleeping!
 /world/proc/TgsTestMerges()
+	CAN_BE_REDEFINED(TRUE)
 	return
 
 /// Returns a list of connected [/datum/tgs_chat_channel]s if TGS is present, null otherwise. This function may sleep if the call to [/world/proc/TgsNew] is sleeping!
 /world/proc/TgsChatChannelInfo()
+	CAN_BE_REDEFINED(TRUE)
 	return
 
 /*
diff --git a/code/game/atoms_movable.dm b/code/game/atoms_movable.dm
index 2f8fe74348d..4326981358f 100644
--- a/code/game/atoms_movable.dm
+++ b/code/game/atoms_movable.dm
@@ -237,6 +237,7 @@
 /// To be removed on step_ conversion.
 /// All this work to prevent a second bump.
 /atom/movable/Move(atom/newloc, direction, glide_size_override = 0, update_dir = TRUE, momentum_change = TRUE)
+	CAN_BE_REDEFINED(TRUE)
 	. = FALSE
 	if(!newloc || newloc == loc)
 		return
diff --git a/code/game/objects/items/cigs.dm b/code/game/objects/items/cigs.dm
index 8325f22e9d1..c0d5687d6b0 100644
--- a/code/game/objects/items/cigs.dm
+++ b/code/game/objects/items/cigs.dm
@@ -428,7 +428,7 @@ LIGHTERS ARE IN LIGHTERS.DM
 	icon_state = "death_cig"
 	butt_type = /obj/item/cigbutt/death
 
-/obj/item/clothing/mask/cigarette/random/New()
+/obj/item/clothing/mask/cigarette/carcinoma/New()
 	list_reagents = list("nicotine" = 40, "dnicotine" = 10, pick("carpotoxin", "toxin", "atrazine") = 1)
 	..()
 
diff --git a/code/modules/antagonists/_common/antag_exfiltration.dm b/code/modules/antagonists/_common/antag_exfiltration.dm
index d057c71162c..42722e05b3b 100644
--- a/code/modules/antagonists/_common/antag_exfiltration.dm
+++ b/code/modules/antagonists/_common/antag_exfiltration.dm
@@ -225,7 +225,7 @@
 	icon_state = "flayer_telepad_base"
 	setup_type = /obj/effect/temp_visual/exfiltration/mindflayer
 
-/obj/item/wormhole_jaunter/extraction/changeling/show_activation_message(mob/user)
+/obj/item/wormhole_jaunter/extraction/mindflayer/show_activation_message(mob/user)
 	user.visible_message("<span class='notice'>[user] sets a strange telepad on the floor. It begins to unfold.</span>",
 					"<span class='notice'>You push a button on [src], and watch as it begins to unfold.</span>")
 
diff --git a/paradise.dme b/paradise.dme
index 9e95ef103e7..aecfceeae50 100644
--- a/paradise.dme
+++ b/paradise.dme
@@ -11,6 +11,7 @@
 // END_PREFERENCES
 // BEGIN_INCLUDE
 #include "__odlint.dm"
+#include "__spacemandmm.dm"
 #include "_maps\__MAP_DEFINES.dm"
 #include "_maps\base_map.dm"
 #include "_maps\map_datums.dm"
@@ -25,7 +26,6 @@
 #include "code\__DEFINES\_math.dm"
 #include "code\__DEFINES\_protection.dm"
 #include "code\__DEFINES\_readme.dm"
-#include "code\__DEFINES\_spacemandmm.dm"
 #include "code\__DEFINES\_tgs_defines.dm"
 #include "code\__DEFINES\_tick.dm"
 #include "code\__DEFINES\_versions.dm"