Is Jack the Ripper a Monster as well as a Mortal?
Yes! The inclusion of the capitalized 'Monstrous' in his typeline makes him a Monster (and thus Evil).
What if the Mortal's location is one where Jack would be silenced? Or disabled?
When Jack the Ripper is cast (before he even enters the realm!), his ability is put on the storyline to resolve in the future, when he enters the realm. Silenced upon entering the realm: His ability is already on the storyline, so it still resolves. (A silenced minion can still kill other minions.) He does lose stealth due to silence. upon entering the : His is already on the , but when it goes to resolve, he cannot actually anyone, since being prevents a from taking any actions granted by an effect. He will also due to being .
Can Jack be cast to a Mortal in a region other than the surface?
Yes, but if cast to the void, he will be banished before the rest of his cast ability can resolve. If summoned underground or underwater (or to any location with an effect that would kill him) he will die before he can complete his task as well, assuming he doesn't immediately gain the ability to survive in that location. This means he will neither Silence nor Kill his prey.
What if I send Jack the Ripper to commit regicide, casting him to the location of my opponent's King of the Realm?
Jack will enter at the King's location and will technically change control briefly to the controller of the King of the Realm, but his ability will already be on the storyline. Jack will then silence and kill the King, and return to your control.
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