When this creature enters, you become the monarch.

When this creature enters, exile target creature an opponent controls until an opponent becomes the monarch.

When Palace Jailer enters the battlefield, you become the monarch.

When Palace Jailer enters the battlefield, exile target creature an opponent controls until an opponent becomes the monarch.

When Palace Jailer enters the battlefield, you become the monarch.

When Palace Jailer enters the battlefield, exile target creature an opponent controls until an opponent becomes the monarch.

When Palace Jailer enters the battlefield, you become the monarch.

When Palace Jailer enters the battlefield, exile target creature an opponent controls until an opponent becomes the monarch.

When Palace Jailer enters the battlefield, you become the monarch.

When Palace Jailer enters the battlefield, exile target creature an opponent controls until an opponent becomes the monarch. (That creature returns under its owner's control.)