More blood tweaks (#6811)

Content.Server/Fluids/Components/PuddleComponent.cs

@@ -54,6 +54,13 @@ namespace Content.Server.Fluids.Components
         [ViewVariables] [DataField("overflowVolume")]
         public FixedPoint2 OverflowVolume = DefaultOverflowVolume;
 
+        /// <summary>
+        ///     How much should this puddle's opacity be multiplied by?
+        ///     Useful for puddles that have a high overflow volume but still want to be mostly opaque.
+        /// </summary>
+        [DataField("opacityModifier")]
+        public float OpacityModifier = 1.0f;
+
         public FixedPoint2 OverflowLeft => CurrentVolume - OverflowVolume;
 
         [DataField("solution")] public string SolutionName { get; set; } = DefaultSolutionName;