Ghasts are invisible! They send out fireballs but you cannot kill or hit them because they are completely invisible.
To reproduce, go to the nether and wait for a ghast to "appear" (you will hear the noises but not see a ghast) and fireballs will be fired towards you
Video attached to show the scariest thing I have ever encountered in Minecraft!
I also notice the last time this was logged was 2016 and it was resolved so please don't resolve this one as it's a new issue and I've seen some other people comment that they have the same issue either invisible ghast or invisible fireballs
Thank you for your report!
We're actually already tracking this issue at MCPE-100425, so I will resolve and link this ticket as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
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