The following manipulations force Big Octo to only shoot rocks during it's third phase, which is usually random.
Perform Octo Clip like in the reference video, make sure to do 2 rolls down into the loading zone. Depending on the number of attempts, you will have to adjust the RNG to match the manipulation at the start of the fight.
Phase 1
Adjust RNG
1st try does a Full dash and an additional roll
2nd try does 1 boot dust and 3 rolls in between the rock attacks
3rd try does 3 rolls in between the rock attacks
4th try does 1 roll less into the fight, no extra rolls
Reflect back the first 3 rocks
Roll twice to the left and position yourself near the corner of the wall
When you hear the sound cue, use boots to the right
Equip Lantern over Boots and light his tail
Walk to the top left corner of the room
Watch the rock patterns to decide how to adjust RNG
If rocks land near the A button, add 2 rolls
If rocks don't land on Link, add 3 rolls
Once the ground starts melting, perform 3 rolls and the additional rolls if any of the above occurs
Phase 2
Dodge his sucking attack by walking to the right
Reflect a boulder
Walk back into the corner
Dodge his sucking attack by walking to the right
Reflect a boulder
Walk back into the corner
Reflect another boulder
Roll four times to the right and twice down
Light his tail
Roll 3 times to the left and position yourself at the bottom of the room just before the camera hits the left side of the room.
Phase 3
It is important to stand still without sliding from the moment the rocks spawn, we need to see where they land and the pattern forms from links position. If rocks are going to land on you then you may dodge them (but you need to make a note that they would have hit you)
If you are never hit by any rocks:
If all the rocks land on the right side of the screen, do 8 Rolls
If any rocks land on the left side of the screen, do 2 rolls
If you are hit by a rock in the 1st wave, Either do 0 rolls or do 1 roll (you may be able to tell by the exact rock pattern which is the correct choice)
If you are hit by a rock in the 2nd wave, do 5 rolls (on rare occasions you will get a pattern that only works with 7 rolls)
Have Boots and Shield equipped, and reset after unfreezing Big Octo and obtaining the lantern
Hold down and use boots in the first room
Use boots in the second room
Phase 1
Hold Shield and move straight up
Roll twice to the left and position yourself near the corner of the wall
When you hear the sound cue, use boots to the right
Equip Lantern over Boots and light his tail
Walk to the top left corner of the room
Phase 2
Dodge his sucking attack by walking to the right
Reflect a boulder
Walk back into the corner
Dodge his sucking attack by walking to the right
Reflect a boulder
Walk back into the corner
Reflect another boulder
Roll four times to the right and twice down
Light his tail
Walk to the bottom left of the room
Phase 3
Depending on what pattern you get on the falling rocks, roll a certain number of times and hold shield while walking towards Octo