Champion ModWith the major update, the new champion was introduced. Here are some information about it.
There are now basically four Kind of Monsters in the game. Normal Monsters, normal champions, strong champions and insane champions. Everyone of them has their unique Attributes such as power, HP, Atk. Speed etc. They look like this in game:
Here are some more information about their spawnrate
While killing champion Monsters you have a chance to obtain certain reward boxes. Below you can see what items and how many of them you can get out of the boxes. The chances are not 100% for all these items.