Task.WaitAll on a list of TransformBlock

Question

I currently have a number of transform blocks running in a sequence a action task then does a wait all for these transform tasks come to completion however it looks very messy and as i add more transform blocks its going to get worse.

 Action<Task> postOrderCompletion = t =>
            {
                Task.WaitAll(EDIFACT_96A_Processor.Completion, EDIFACT_97A_Processor.Completion, ErrorProcessor.Completion);
                SetForProcessing.Complete();
            };

Is there a wait i can wait all for a list of transform blocks to complete?

var listOfTransformBlocks = new List<TransformBlock<Invoice_Base[], Invoice_Completed>>();