To attack, or not to attack, part 2

In a previous blog post I asked a question about what happens when a Jackal Familiar is enchanted with Furor of the Bitten. This is a similar question, but with a slightly different twist:

Assume that a Master of Cruelties is enchanted by Furor of the Bitten. What happens?

This is closely related to the other situation, but the difference is now that rather than the creature being unable to attack alone, this one can only attack alone. Thus the question becomes: Can you attack with another creature, or are you forced to attack with Master of Cruelties each turn (if it's otherwise able), precluding any other creature from attacking?

This is once again a situation where many players, even very experienced ones, get it wrong (and may cause a considerable amount of disagreement.) The correct answer is that yes, Master of Cruelties must attack each turn (if there's nothing else stopping it, eg. summoning sickness) and thus nothing else can attack.

Rule 508.1d of the Comprehensive Rules (which I quoted in the other blog post) deals with this situation. It basically amounts to:

When declaring attackers:

1. Restrictions must not be disobeyed.
2. The amount of requirements being obeyed must be maximized (without disobeying any restriction.)
3. Any other declaration of attackers is illegal.

In this particular case a declaration of attackers where Master of Cruelties is attacking obeys more requirements (without disobeying any restrictions) than a declaration where it's not attacking. Therefore it's the only legal declaration.

(Sometimes it may happen that there are several possible declarations that obey the same number of requirements. In this case the player can freely choose between one of them. However, as stated, those are the only legal ones, and one of them must be chosen.)

But wait, there is more. Here's an even more complicated twist to the problem:

Suppose you control Master of Cruelties (not enchanted by anything) and some other creatures, and your opponent casts Aggravate. What happens?

The key to resolve this situation is to realize that an effect that says "each creature attacks if able" is placing a requirement on each such creature individually, and the amount of requirements being obeyed must be maximized.

This means that if you control two creatures (one of them being Master of Cruelties), then you can choose which one attacks. (This is an example where two different declarations of attackers obeys the same amount of requirements, and thus you can choose one of them.)

However, if you control more than two creatures, then the only legal declaration is one where all the other creatures except Master of Cruelties attack (because this declaration obeys the most requirements.)

(Bonus question: What happens in the above situation if Master of Cruelties is enchanted with Furor of the Bitten?)