The problem with Apoo's attacks isn't that it's invisible, it's that it's intangible. How do you guard yourself against sound?
That's not true.... first of all, they can evade damage through 3 ways:
1- Using armament haki, if it's strong enough, the explosions, the cuts, punch... etc won't work.
2- Using Observation Haki + Being SOOO fast in reflexes/reaction in order to dodge LEFT or Right the moment he directs his attack through those sound waves
3- To get out of Range by being way too far... since Apoo basically admitted it has a range...
Can you tell the difference between Apoo's attacks and Sanji and Shiryu being invisible?
Apples and oranges...
The difference in how they are invisible, doesn't change the METHOD in dealing with them... and dealing with them ALL is exactly through Number 1 and Number 2 in the comment I just gave above...
So:
- Either you just cover yourself with Armament and protect yourself (you'll fail if your armament isn't strong enough)
- Or You have to have Great observation to determine the TIMING of the attack, and have FAST Reaction and reflexes and BE ON POINT, in order to back up your observation by dodging in the time of the attack.. (If your speed is SLOWER than the attack, or your observation during the moment of attack was NOT Top notch, you'll fail)
However, getting out of range can work, but that means it's the option of WITHDRAWING from the fight...
With Apoo, With Stealth Black, With Shiryuu, the METHOD is the same...