diff --git a/code/datums/action.dm b/code/datums/action.dm
index 52e96b4d63b..79173b4c4a8 100644
--- a/code/datums/action.dm
+++ b/code/datums/action.dm
@@ -69,9 +69,6 @@
 	Trigger()
 	return FALSE
 
-/datum/action/proc/Process()
-	return
-
 /datum/action/proc/override_location() // Override to set coordinates manually
 	return
 
diff --git a/code/datums/components/_component.dm b/code/datums/components/_component.dm
index 27ee68f0189..4c4ea93241a 100644
--- a/code/datums/components/_component.dm
+++ b/code/datums/components/_component.dm
@@ -259,20 +259,6 @@
 /datum/component/proc/InheritComponent(datum/component/C, i_am_original)
 	return
 
-
-/**
-  * Called on a component when a component of the same type was added to the same parent with [COMPONENT_DUPE_SELECTIVE]
-  *
-  * See [/datum/component/var/dupe_mode]
-  *
-  * `C`'s type will always be the same of the called component
-  *
-  * return TRUE if you are absorbing the component, otherwise FALSE if you are fine having it exist as a duplicate component
-  */
-/datum/component/proc/CheckDupeComponent(datum/component/C, ...)
-	return
-
-
 /**
   * Callback Just before this component is transferred
   *
@@ -443,12 +429,6 @@
 					var/list/arguments = raw_args.Copy()
 					arguments[1] = new_comp
 					var/make_new_component = TRUE
-					for(var/i in GetComponents(new_type))
-						var/datum/component/C = i
-						if(C.CheckDupeComponent(arglist(arguments)))
-							make_new_component = FALSE
-							QDEL_NULL(new_comp)
-							break
 					if(!new_comp && make_new_component)
 						new_comp = new nt(raw_args)
 		else if(!new_comp)
diff --git a/code/datums/position_point_vector.dm b/code/datums/position_point_vector.dm
index f1e5ffc05b5..1cad3b52899 100644
--- a/code/datums/position_point_vector.dm
+++ b/code/datums/position_point_vector.dm
@@ -23,7 +23,7 @@
 	return ATAN2((b.y - a.y), (b.x - a.x))
 
 /// For positions with map x/y/z and pixel x/y so you don't have to return lists. Could use addition/subtraction in the future I guess.
-/datum/position	
+/datum/position
 	var/x = 0
 	var/y = 0
 	var/z = 0
@@ -68,7 +68,7 @@
 	return new /datum/point_precise(src)
 
 /// A precise point on the map in absolute pixel locations based on world.icon_size. Pixels are FROM THE EDGE OF THE MAP!
-/datum/point_precise		
+/datum/point_precise
 	var/x = 0
 	var/y = 0
 	var/z = 0
@@ -83,7 +83,7 @@
 	return p
 
 /// First argument can also be a /datum/position or /atom.
-/datum/point_precise/New(_x, _y, _z, _pixel_x = 0, _pixel_y = 0)	
+/datum/point_precise/New(_x, _y, _z, _pixel_x = 0, _pixel_y = 0)
 	if(istype(_x, /datum/position))
 		var/datum/position/P = _x
 		_x = P.x
@@ -134,11 +134,11 @@
 
 /datum/point_precise/vector
 	/// Pixels per iteration
-	var/speed = 32				
+	var/speed = 32
 	var/iteration = 0
 	var/angle = 0
 	/// Calculated x movement amounts to prevent having to do trig every step.
-	var/mpx = 0					
+	var/mpx = 0
 	/// Calculated y movement amounts to prevent having to do trig every step.
 	var/mpy = 0
 	var/starting_x = 0 //just like before, pixels from EDGE of map! This is set in initialize_location().
@@ -158,7 +158,7 @@
 	starting_z = z
 
 /// Same effect as initiliaze_location, but without setting the starting_x/y/z
-/datum/point_precise/vector/proc/set_location(tile_x, tile_y, tile_z, p_x = 0, p_y = 0) 
+/datum/point_precise/vector/proc/set_location(tile_x, tile_y, tile_z, p_x = 0, p_y = 0)
 	if(!isnull(tile_x))
 		x = ((tile_x - 1) * world.icon_size) + world.icon_size * 0.5 + p_x + 1
 	if(!isnull(tile_y))
@@ -214,9 +214,6 @@
 		v.increment(multiplier * amount)
 	return v
 
-/datum/point_precise/vector/proc/on_z_change()
-	return
-
 /datum/point_precise/vector/processed //pixel_speed is per decisecond.
 	var/last_process = 0
 	var/last_move = 0
diff --git a/code/datums/spell.dm b/code/datums/spell.dm
index 3f5c82772e3..4199efa023e 100644
--- a/code/datums/spell.dm
+++ b/code/datums/spell.dm
@@ -114,7 +114,6 @@ GLOBAL_LIST_INIT(spells, typesof(/obj/effect/proc_holder/spell))
 	var/smoke_type = SMOKE_NONE
 	var/smoke_amt = 0
 
-	var/critfailchance = 0
 	var/centcom_cancast = TRUE //Whether or not the spell should be allowed on the admin zlevel
 	/// Whether or not the spell functions in a holy place
 	var/holy_area_cancast = TRUE
@@ -360,10 +359,7 @@ GLOBAL_LIST_INIT(spells, typesof(/obj/effect/proc_holder/spell))
 	if(sound)
 		playMagSound()
 
-	if(prob(critfailchance))
-		critfail(targets)
-	else
-		cast(targets, user = user)
+	cast(targets, user = user)
 	after_cast(targets, user)
 	if(action)
 		action.UpdateButtonIcon()
@@ -434,9 +430,6 @@ GLOBAL_LIST_INIT(spells, typesof(/obj/effect/proc_holder/spell))
 /obj/effect/proc_holder/spell/proc/cast(list/targets, mob/user = usr)
 	return
 
-/obj/effect/proc_holder/spell/proc/critfail(list/targets)
-	return
-
 /obj/effect/proc_holder/spell/proc/revert_cast(mob/user = usr) //resets recharge or readds a charge
 	cooldown_handler.revert_cast()
 	custom_handler?.revert_cast(user, src)
diff --git a/code/datums/spell_cooldown/spell_cooldown.dm b/code/datums/spell_cooldown/spell_cooldown.dm
index aa08e9491e4..3d320bdca8a 100644
--- a/code/datums/spell_cooldown/spell_cooldown.dm
+++ b/code/datums/spell_cooldown/spell_cooldown.dm
@@ -29,16 +29,12 @@
 /datum/spell_cooldown/proc/should_end_cooldown()
 	return !is_on_cooldown()
 
-/datum/spell_cooldown/proc/end_recharge()
-	return
-
 /datum/spell_cooldown/process()
 	if(!spell_parent.action)
 		stack_trace("[spell_parent.type] ended up with a null action")
 		return PROCESS_KILL
 	spell_parent.action.UpdateButtonIcon()
 	if(should_end_cooldown())
-		end_recharge()
 		return PROCESS_KILL
 
 
diff --git a/code/game/gamemodes/game_mode.dm b/code/game/gamemodes/game_mode.dm
index 48d89f2eaba..3e4a3ad4e6b 100644
--- a/code/game/gamemodes/game_mode.dm
+++ b/code/game/gamemodes/game_mode.dm
@@ -106,9 +106,6 @@
 		return 1
 	return 0
 
-/datum/game_mode/proc/cleanup()	//This is called when the round has ended but not the game, if any cleanup would be necessary in that case.
-	return
-
 /datum/game_mode/proc/declare_completion()
 	var/clients = 0
 	var/surviving_humans = 0
diff --git a/code/modules/mob/living/carbon/alien/alien_life.dm b/code/modules/mob/living/carbon/alien/alien_life.dm
index 4c25a4eadc8..4c13daa7af0 100644
--- a/code/modules/mob/living/carbon/alien/alien_life.dm
+++ b/code/modules/mob/living/carbon/alien/alien_life.dm
@@ -26,9 +26,6 @@
 	breath.toxins -= toxins_used
 	breath.oxygen += toxins_used
 
-	//BREATH TEMPERATURE
-	handle_breath_temperature(breath)
-
 /mob/living/carbon/alien/handle_status_effects()
 	..()
 	//natural reduction of movement delay due to stun.
diff --git a/code/modules/mob/living/carbon/carbon_life.dm b/code/modules/mob/living/carbon/carbon_life.dm
index 176ac304310..0a59c7b113b 100644
--- a/code/modules/mob/living/carbon/carbon_life.dm
+++ b/code/modules/mob/living/carbon/carbon_life.dm
@@ -100,7 +100,7 @@
 		if(ishuman(src) && !internal && environment.temperature < 273 && environment.return_pressure() > 20) //foggy breath :^)
 			new /obj/effect/frosty_breath(loc, src)
 
-//Third link in a breath chain, calls handle_breath_temperature()
+//Third and last link in a breath chain
 /mob/living/carbon/proc/check_breath(datum/gas_mixture/breath)
 	if(status_flags & GODMODE)
 		return FALSE
@@ -181,15 +181,8 @@
 			if(prob(20))
 				emote(pick("giggle","laugh"))
 
-	//BREATH TEMPERATURE
-	handle_breath_temperature(breath)
-
 	return TRUE
 
-//Fourth and final link in a breath chain
-/mob/living/carbon/proc/handle_breath_temperature(datum/gas_mixture/breath)
-	return
-
 /mob/living/carbon/proc/get_breath_from_internal(volume_needed)
 	if(internal)
 		if(internal.loc != src)
diff --git a/code/modules/projectiles/guns/medbeam.dm b/code/modules/projectiles/guns/medbeam.dm
index a61932cafdf..815ad91cb34 100644
--- a/code/modules/projectiles/guns/medbeam.dm
+++ b/code/modules/projectiles/guns/medbeam.dm
@@ -105,9 +105,6 @@
 	qdel(dummy)
 	return TRUE
 
-/obj/item/gun/medbeam/proc/on_beam_hit(mob/living/target)
-	return
-
 /obj/item/gun/medbeam/proc/on_beam_tick(mob/living/target)
 	if(ishuman(target))
 		var/mob/living/carbon/human/H = target