Asta_Black-Clover guess from the pictures I posted in the comments and see who is right and who is wrong.
Asta_Black-Clover BreadstickBoi23 yep and had to install a mod that adds marvel characters in it to make the doctor doom chosen event in Fortnite. luckily it had doctor doom in it with the mod.
Asta_Black-Clover I had to put a command block at one of the corners at the cauldron and placed a green shulker box under the cauldron and the command block clears the inventory and you loot the shulker box and grab the items.