PIglin Brutes are 100% invisible and have no hitbox in the bastions. I was speedrunning and saw a piglin approaching me, i threw gold and started trading, but then i saw that someone else took the gold, and then obisidian just randomy droped out of knowwhere, i tried hitting the entity but i could, nevertheless i could 100% hear the steps and piglin brute sounds, i have subtitles on. The only way i could kill piglin brutes was using a fire and lava, i eventually got killed out of nowhere, also you cant see when invisible piglin or brute is on fire or taking any damage, you cant interact with them in any way, but they can. It was a pretty good going speedrun, i was on 9 mins when i died, had a bunch of pearls and full iron