Best way to model a two-sided playing card?

Question

What is the best way to model a two-sided playing card in Blender 3D which is both performant and flexible?

Each side of the card must have its own distinct texture, it should have some level of thickness (which I believe rules out a Plane), should have very accurate collision detection, and possibly be deformable (card "bends" a bit when it hits the table).

There may be hundreds of cards, each of which may have its own distinct textures (this isn't a normal deck of cards).

The models/textures will most likely end up in Unity 3D.

Answer 1

A squished cube, or two planes with opposite facing normals, depending on whether you need an actual thickness or not. You mention Unity, so I'd reckon you don't actually need thickness. Two planes with opposing normals, and enabled backface culling so you don't get z-fighting, should do the trick.