You need to combine MAGIC pins for it to work. Say, if I had two Dancing Inferno MAGIC pins (I wish), I could combine them into a 2 star Dancing Inferno MAGIC pin. But, if I had two blue tiki pins, which are non-MAGIC pins, I couldn't combine them.
See, when you combine MAGIC pins, it strengthens the effect of the MAGIC. Like, your inferno would go for longer. Hope that helps.