Gatstaf Shepherd // Gatstaf Howler

Oracle Text

[Gatstaf Shepherd]
At the beginning of each upkeep, if no spells were cast last turn, transform this creature.

[Gatstaf Howler]
Intimidate (This creature can't be blocked except by artifact creatures and/or creatures that share a color with it.)
At the beginning of each upkeep, if a player cast two or more spells last turn, transform this creature.