Is it up to the attacker and defender to decide where to allocate their damage among battling units? Example:

Bob is attacking Joe's Kingdom.

Bob has 2 attacking unit cards: Card A has 5 power and 6 HP, card B has 2 power and 3 HP.

Joe declares both his cards as defenders: Card X has 3 power and 5 HP, card Y has 1 power and 3 HP.

Can Bob choose where to assign damage amongst cards X and Y? Could he choose to "wipe out" card Y and leave card X damaged, or the other way around? Or, does Joe get to choose where it goes since he's defending?

When Joe then assigns his damage to the attacking units, can he choose which unit to assign how much to, or does Bob get to choose that?

If this scenario is not the case, then in what order do you assign damage to units? Weakest first, strongest first, or some other way? The rules state that the untis attack and defend as a whole, not as indiviudals, but I am kinda confused on this one detail.

Thanks!

This too was already covered. It's fine though, just keep asking whenever anything's not clear.

Bob has a total of 7 combat damage to distribute (the combined power of his attackers). He can distribute it any way he likes among the defenders, so he will most likely destroy one and damage the other. He could assign all the damage to just one of them, in anticipation of an unknown cancellation effect for example, or because he doesn't want the other to be damaged for some reason. It's completely up to him which defending unit gets assigned how much of the 7 damage points, he is in no way forced to damage/destroy the strongest or weakest first. He cannot however assign any damage to the kingdom zone. For that, he would first have to assign enough damage to each defending unit to destroy it.

For Joe it's the same, except he couldn't possibly damage Bob's capital in the first place, since he is the defender. He distributes a total of 4 combat damage among the attacking units however he wants to. He can damage them both (dealing 2 to each, or 1 to one of them and 3 to the other), or destroy B and damage A, or just damage A and leave B untouched.