C-Xbot

"???" Elements: Shadow, Mech, Crystal, Poison

This monster can be bred with two Double Elements.

Kazilleon + Bellowfish

Boodoo + Dragong

Arackulele + Fung Pray

However, it can be bred with a Single Element and a Triple Element.

Pipgan + Grumpyre

Triochoir + Reebro

Skulltar + Jeeode

Gockonspiel + Humbug