Magus of the Mist is a Unit.
How to Get Edit
|•||On Play:||"It's more real than you think."|
The dragon is very powerful, but Magus is very weak, as even a one cost torch can kill it. Therefore, it is best to protect Magus with aegis, or return it to hand, along other methods, to protect it. Once the dragon dies naturally, Magus does not have to be played as carefully.
You may silence or transform your own Magus to allow your Dragon to live on.