When this creature enters, if you control two or more Gates, target creature an opponent controls gets -2/-2 until end of turn.
Illustrated by Volkan Baǵa · Pioneer Masters · #115
There are no rulings for Ubul Sar Gatekeepers.
When this creature enters, target creature an opponent controls gets -1/-1 until end of turn.
When this creature enters, target creature an opponent controls gets -2/-2 until end of turn if that opponent controls no other creatures.
Whenever another creature you control enters, target creature an opponent controls gets -1/-1 until end of turn.
Whenever a creature you control explores, target creature an opponent controls gets -2/-2 until end of turn.
Morbid — When this creature enters, target creature an opponent controls gets -1/-1 until end of turn. If a creature died this turn, that creature gets -13/-13 until end of turn instead.