If {manavault} is a creature with all creature types, doesn't that mean that it is also a wall. I thought that all walls had defender to fix the older walls that were not printed with defender on them.
Thank you, I know they changed oracle text on the old walls to add defender but couldn't find any ruling stating that walls had to have defender and was slightly confused. I think that clears it up. They introduce new abilities and rules as they see fit and change the rest of the game to match the new set. Maybe that will be later in the Theros block, a wall without defender to stop {prowler's helm}
Wall: A creature type with no particular rules meaning. Older cards with the Wall creature type but without defender had an unwritten ability that precluded them from attacking. Those cards have received errata in the Oracle card reference to have defender. Some older cards that referenced the Wall creature type have also received errata. See Defender.