Even if a player can afford it, they cannot launch an attack with more than 6 combat dice per attack.
Example: 7 gun ammo will only give you 6 attack dice.
All the rubble cards used are discarded at the end of the attack.
When the attack is over, if some damage has not been assigned to an enemy, it is discarded and cannot be used for another attack.
An attacker can launch another attack if he has a rubble card that allows him to. In this case, the player launches a new attack using new rubble cards and follows the same procedure.