diff --git a/code/__DEFINES/subsystems.dm b/code/__DEFINES/subsystems.dm
index ff463fb44c6..155a2b16888 100644
--- a/code/__DEFINES/subsystems.dm
+++ b/code/__DEFINES/subsystems.dm
@@ -198,6 +198,7 @@
 #define FIRE_PRIORITY_STATPANEL 390
 #define FIRE_PRIORITY_CHAT 400
 #define FIRE_PRIORITY_RUNECHAT 410
+#define FIRE_PRIORITY_MOUSE_ENTERED 450
 #define FIRE_PRIORITY_OVERLAYS 500
 #define FIRE_PRIORITY_EXPLOSIONS 666
 #define FIRE_PRIORITY_TIMER 700
diff --git a/code/controllers/subsystem/mouse_entered.dm b/code/controllers/subsystem/mouse_entered.dm
new file mode 100644
index 00000000000..6dc8d995a52
--- /dev/null
+++ b/code/controllers/subsystem/mouse_entered.dm
@@ -0,0 +1,23 @@
+/// Defers MouseEntered inputs to only apply to the most recently hovered over atom in the tick
+SUBSYSTEM_DEF(mouse_entered)
+	name = "MouseEntered"
+	wait = 1
+	flags = SS_NO_INIT | SS_TICKER
+	priority = FIRE_PRIORITY_MOUSE_ENTERED
+	runlevels = RUNLEVELS_DEFAULT | RUNLEVEL_LOBBY
+
+	var/list/hovers = list()
+
+/datum/controller/subsystem/mouse_entered/fire()
+	for (var/hovering_client in hovers)
+		var/atom/hovering_atom = hovers[hovering_client]
+		if (isnull(hovering_atom))
+			continue
+
+		hovering_atom.on_mouse_enter(hovering_client)
+
+		// This intentionally runs `= null` and not `-= hovering_client`, as we want to prevent the list from shrinking,
+		// which could cause problems given the heat of MouseEntered.
+		// Lummox has teased this for 515: https://www.byond.com/forum/post/2621745
+		// ...though you're most likely reading this on BYOND version 600.
+		hovers[hovering_client] = null
diff --git a/code/game/atoms.dm b/code/game/atoms.dm
index b12cd643804..73ae564f216 100644
--- a/code/game/atoms.dm
+++ b/code/game/atoms.dm
@@ -2101,11 +2101,19 @@
 
 	return TRUE
 
-//Update the screentip to reflect what we're hoverin over
 /atom/MouseEntered(location, control, params)
-	. = ..()
+	SSmouse_entered.hovers[usr.client] = src
+
+/// Fired whenever this atom is the most recent to be hovered over in the tick.
+/// Preferred over MouseEntered if you do not need information such as the position of the mouse.
+/// Especially because this is deferred over a tick, do not trust that `client` is not null.
+/atom/proc/on_mouse_enter(client/client)
+	SHOULD_NOT_SLEEP(TRUE)
+
+	var/mob/user = client?.mob
+
 	// Screentips
-	var/datum/hud/active_hud = usr.hud_used
+	var/datum/hud/active_hud = user?.hud_used
 	if(active_hud)
 		if(!active_hud.screentips_enabled || (flags_1 & NO_SCREENTIPS_1))
 			active_hud.screentip_text.maptext = ""
diff --git a/code/modules/client/client_procs.dm b/code/modules/client/client_procs.dm
index 9588a786128..a1bf1831fe3 100644
--- a/code/modules/client/client_procs.dm
+++ b/code/modules/client/client_procs.dm
@@ -548,6 +548,7 @@ GLOBAL_LIST_INIT(blacklisted_builds, list(
 
 	active_mousedown_item = null
 	SSambience.remove_ambience_client(src)
+	SSmouse_entered.hovers -= src
 	QDEL_NULL(view_size)
 	QDEL_NULL(void)
 	QDEL_NULL(tooltips)
diff --git a/tgstation.dme b/tgstation.dme
index 2b799411731..6151bead8ad 100644
--- a/tgstation.dme
+++ b/tgstation.dme
@@ -486,6 +486,7 @@
 #include "code\controllers\subsystem\minor_mapping.dm"
 #include "code\controllers\subsystem\mobs.dm"
 #include "code\controllers\subsystem\moods.dm"
+#include "code\controllers\subsystem\mouse_entered.dm"
 #include "code\controllers\subsystem\nightshift.dm"
 #include "code\controllers\subsystem\npcpool.dm"
 #include "code\controllers\subsystem\overlays.dm"