You can also use the black backed 3 in a regular red deck for a spectacular 'back' reveal using forces.
Here's something else to try with the black cards...
It's tricky, and I ain't tried it yet, but try using a combo of Elmsley and Flustration counts with black cards/regular cards... in principle, I think you could do an awesome 'twisting' style effect—where at the end ALL the cards turn black. Very visual.
But basically, even just shuffling the tigers makes me all gooey inside
