A: To refresh, the Assassin reads:

If someone has the Crown in play, that player must immediately discard it.
If no one has the Crown in play, discard any Object in play or a randomly chosen card from another player’s hand.

If you have the Crown in play, and you play the Assassin card, sadly for you, the Assassin is required to take out the Crown. No ifs, ands, or buts.

On the other hand, if the Crown is NOT in play, you have the option whether to take out an object in play, or target another player’s random in-hand card.

It may seem cruel or counter-intuitive for you to be required to do something detrimental to yourself, but that only happens in the first case. That’s the spirit of the Assassin, its primary aim is to kill the monarch – but with no Crown in play, the Assassin actually becomes a much more versatile, and therefore more powerful card. It’s interesting how timing can change how powerful certain cards are in Get the MacGuffin, isn’t it?!