So... How many monsters actually change when evolving?

I'm asking because the majority of monsters I've evolved have never changed types or looks, they just upgrade and get better stats.

However I have an Assassin Dark Voidling I just recently took from 2 star to 3 star and he actually changed into an Assassin Possessed Mine.

I'm a little disappointed because I loved the Voidling basic attack, which has a 30% chance to additionally strike and had a chance of critical hits.
The new Mine deals physical and magical damage with a chance to block beneficial effects; it also has healing.

Any one know of any others that completely change upon evolving or is this possibly a bug?

Hello Watchers, the same happened to me a while ago.... I'm still thinking that this is an actual bug.....

Yeah it was curious enough that I took a screenshot right before I evolved it for posterity lol.

Attachment 1046

That so sooo weird!!!! I think it is a bug. report it