Submarines, items and characters that reach a depth of 300,000 units (~4000 m) are automatically disabled. Avoids the unnecessary cost of updating entities that are way too deep to be reached by anyone.

Barotrauma/BarotraumaShared/Source/Map/SubmarineBody.cs

@@ -16,8 +16,6 @@ namespace Barotrauma
     class SubmarineBody
     {
         public const float DamageDepth = -30000.0f;
-        //private const float PressureDamageMultiplier = 0.001f;
-
         private const float DamageMultiplier = 50.0f;
 
         private const float Friction = 0.2f, Restitution = 0.0f;