diff --git a/actions.py b/actions.py
index 037f339..08136d3 100644
--- a/actions.py
+++ b/actions.py
@@ -1,6 +1,6 @@
 from __future__ import annotations
 
-from typing import Optional, Tuple, TYPE_CHECKING
+from typing import Optional, Tuple, TYPE_CHECKING, overload
 
 if TYPE_CHECKING:
     from engine import Engine
@@ -17,6 +17,7 @@ class Action:
         """Return the engine this action belongs to."""
         return self.entity.gamemap.engine
 
+    @overload
     def perform(self) -> None:
         """Perform this action with the objects needed to determine its scope.
 
@@ -26,7 +27,6 @@ class Action:
 
         This method must be overwritten by Action subclasses.
         """
-        raise NotImplementedError()
 
 
 class EscapeAction(Action):
@@ -51,9 +51,6 @@ class ActionWithDirection(Action):
         """Return the blocking entity at this action's destination."""
         return self.engine.game_map.get_blocking_entity_at_location(*self.dest_xy)
 
-    def perform(self) -> None:
-        raise NotImplementedError()
-
 
 class MeleeAction(ActionWithDirection):
     def perform(self) -> None:
diff --git a/components/ai.py b/components/ai.py
index e3997be..83aa356 100644
--- a/components/ai.py
+++ b/components/ai.py
@@ -10,9 +10,6 @@ from components.base_component import BaseComponent
 
 
 class BaseAI(Action, BaseComponent):
-    def perform(self) -> None:
-        raise NotImplementedError()
-
     def get_path_to(self, dest_x: int, dest_y: int) -> List[Tuple[int, int]]:
         """Compute and return a path to the target position.
 
@@ -40,4 +37,4 @@ class BaseAI(Action, BaseComponent):
         path: List[List[int]] = pathfinder.path_to((dest_x, dest_y))[1:].tolist()
 
         # Convert from List[List[int]] to List[Tuple[int, int]].
-        return [(index[0], index[1]) for index in path]
\ No newline at end of file
+        return [(index[0], index[1]) for index in path]
diff --git a/input_handlers.py b/input_handlers.py
index 17fedd7..609d8ef 100644
--- a/input_handlers.py
+++ b/input_handlers.py
@@ -26,9 +26,6 @@ class EventHandler(tcod.event.EventDispatch[Action]):
             self.engine.handle_enemy_turns()
             self.engine.update_fov()
 
-    def ev_quit(self, event: tcod.event.Quit) -> Optional[Action]:
-        raise SystemExit()
-
     def ev_keydown(self, event: tcod.event.KeyDown) -> Optional[Action]:
         action: Optional[Action] = None