Once an attack is legally declared, the defender picking up Stealth wont matter.
Basically, just ignore that the character has that ability when determining which character you’re attacking.
They cancel each other out. An attacker is not able to fulfill both conditions, therefore the attacking player can choose a defender as normal.
The opponent can choose to attack any available target; they essentially cancel each other out.
Brave is a new keyword ability that helps some characters protect the rest of their team. When
choosing which enemy to attack, you must choose one with brave if possible.
You choose one of them to attack.
No, and in fact you can’t even if you want to. Brave doesn’t override the rules for attacking
tapped/untapped characters. If your opponent has any tapped characters you must attack one
of them. If a tapped character had brave, you would have to attack that one if you could.
If two or more characters have Brave, the attacking player can choose between them.
Stealth is a new keyword ability that lets some characters strike from the shadows without fear
of reprisal. When choosing which enemy to attack, you must attack a character without stealth
if able.
Stealth doesn’t override the rules for attacking tapped/untapped characters. Since the
tapped character is the only one that can be attacked, that’s where your attack is headed.
Brave and stealth essentially cancel each other out. You must attack that character if able,
and you must attack other characters if able. This basically means you must attack a character
you can attack, the same as if those abilities weren’t there.