I heard Hearthstone was made in Unity 3d, so my question goes, the cards, are they prefabs for gameobjects, or ex. GUI.Box?
I can pretty much promise you they won’t be using GUI.Box…
Most likely something like Scaleform, but that’s just a guess (as will be any other reply you receive on here).
For anyone who wondering how to achieve same Hearthstone card effects with custom shader on their game, my new plugin Ultimate Unlit & UI is just arrived to the store. For demo and other details please check: http://forum.unity3d.com/threads/released-ultimate-unlit-ui-hearthstone-inspired-multilayer-shader.316310/