diff --git a/core/actors/_base_actor.py b/core/actors/_base_actor.py
index ea8793a0..34b1b672 100644
--- a/core/actors/_base_actor.py
+++ b/core/actors/_base_actor.py
@@ -3,6 +3,7 @@
 from typing import Union, get_args, get_origin
 
 from core.commands.base import Command
+from core.events.base import Event
 from core.interfaces.abstract_actor import AbstractActor, Ask, Message
 from core.queries.base import Query
 from infrastructure.event_dispatcher.event_dispatcher import EventDispatcher
@@ -70,19 +71,27 @@ def _unregister_events(self):
             self._mailbox.unregister(event, self.on_receive)
 
     def _discover_events(self):
+        allowed_types = (Event, Query, Command)
         sig = inspect.signature(self.on_receive)
-        params = list(sig.parameters.values())
+        params = sig.parameters.values()
 
-        if len(params) < 1:
+        if not params:
             return []
 
-        event_type = params[0].annotation
+        event_type = next(iter(params)).annotation
 
-        events = []
+        events = (
+            get_args(event_type) if get_origin(event_type) is Union else [event_type]
+        )
 
-        if get_origin(event_type) is Union:
-            events = get_args(event_type)
-        else:
-            events = [event_type]
+        invalid_events = [
+            event for event in events if not issubclass(event, allowed_types)
+        ]
+
+        if invalid_events:
+            raise RuntimeError(
+                f"Disallowed events: {', '.join(e.__name__ for e in invalid_events)}. "
+                f"Must be subclasses of {allowed_types}."
+            )
 
         return list(set(events))