Monarch

Monarch is a term used to describe the five monsters with "Monarch" in their card names. These cards are Zaborg the Thunder Monarch, Thestalos the Firestorm Monarch, Mobius the Frost Monarch, Granmarg the Rock Monarch, and Riser the Wind Monarch. Each has a unique ability that activates upon the Tribute Summon of said card. Another similarity that these cards share is that they are each six-star monsters (except for Zaborg, which is, in fact, a five-star monster).