ok so this should be the way to go

interfaces/IDamageable.cs

@@ -4,5 +4,6 @@ namespace Movementtests.interfaces;
 
 public interface IDamageable
 {
+    event Action<IDamageable, float> DamageTaken;
     float TakeDamage(RDamage damage);
 }

interfaces/IHealthable.cs

@@ -1,6 +1,11 @@
+using System;
+
 namespace Movementtests.interfaces;
 
 public interface IHealthable
 {
-    void ReduceHealth(float amount);
+    event Action<IHealthable, float> HealthChanged;
+    event Action<IHealthable> HealthDepleted;
+    
+    void ReduceHealth(IDamageable source, float amount);
 }

interfaces/IKillable.cs

@@ -2,5 +2,5 @@ namespace Movementtests.interfaces;
 
 public interface IKillable
 {
-    void Kill();
+    void Kill(IHealthable source);
 }