Aspects of a storage device including at least one die and a controller are provided that allow superblock formation using surplus block pairs when bad blocks occur. After the controller forms a superblock including a first block in a first plane of the die and a second block in a second plane of the die, the controller identifies the first block as a bad block and switches the second block into a surplus state (or vice-versa). The controller then forms a new superblock from blocks in a spare pool. When the number of blocks is equal to a superblock threshold, the controller attempts to pair the surplus block with another surplus block from the opposite plane according to a die sequence. If the attempt to pair is successful, the controller adds the pair to the spare pool; otherwise, the surplus block is not added to the spare pool.