killing Guardian with potion of harming + missing splash potion texture in air

First I tried kill Guardian in survival with no armors and no sword
it killed me i go to creative and i try kill it with diamond and others swords and fist no damage then I tried with potion of harming but then game crashes. I retried it and it wont happen but when i tried kill it again with potion of harming game crashes and that save doesn't work. I also tried other splash potions to guardian they all worked + when you throw splash and when potion is in air it will have missing texture

1. throw splash potion of harming to Guardian