Splatoon 3: Hero Mode: Part 37: Splash the Block Party
This stage has a much greater emphasis on using Soaker Blocks. You will need to literally build bridges using these things to get across.
Remember that they will often expand outward in the direction that the first block is pointing towards, but this will often change as more of them come out. Even then, make sure that, if you have to use Smallfry to ink a Soaker Block, make sure he's not inking the same side that a new one will come out from.
Also remember that a Soaker Block will hold itself out for as long as it stays ink. If you don't shoot the first block after a few seconds, it will slowly start to regress back to normal, which might cause you to fall depending on where this happens.
Octarians can also control these blocks with their own ink. In that case, just keep inking the Soaker Block until it turns into your ink's color, and make sure the Octarian can't take them back.