From the Kingdom Hearts Wiki: A world of information not accessible by Gummiship
In Kingdom Hearts III, Cubic Stream is the basic Shotlock of the Nano Gear Keyblade and has a max lock of 23. When activated, Sora hovers in the air and launches a stream of block-like projectiles careening towards the enemies, with the amount of projectiles depending on the number of locks.
Learning Cubic Stream
Kingdom Hearts III