Borromini, Tormented Architect

Cumulative Upkeep {w}{u}{1} , Defender
At the Beginning of all turns, create two 0/3 walls with defender.
At the end of your opponent turn, if you control more than six walls create a 0/7 Legendary artifact creature called "San Carlino" with the following abilities: (All creatures assigned damage with their toughness rather than its power and can attack as though it didn't have defender)