Redthorn didn't experience any of those things in reality, however he was experiencing the pain he would have felt if he experienced such torture.
Even Esdras felt sick to his stomach seeing Redthorn convulsing and writhing on the ground. He understood one thing for sure now, the infernal pact was indeed the real thing.
He knew that before, but seeing it firsthand was different than just reading an item description.
The torture lasted only a minute in reality but the goblin felt as if an entire lifetime had passed already.
"I'm sorry, please… I will tell you everything I know." The goblin looked at him with the look of fear and realization.
He realized that the contract he signed recklessly, was actually binding. He knew about magic items for sure, but he had never seen one before. And even if he did, he would not have recognized the infernal pact for what it was.