Torture Chamber is one of those cards players keep asking about. Here is, in plain words, what its official text says, the rulings published by Wizards of the Coast, and the combos players actually run.

Official card text

At the beginning of your upkeep, put a pain counter on this artifact. At the beginning of your end step, this artifact deals damage to you equal to the number of pain counters on it. , , Remove all pain counters from this artifact: It deals damage to target creature equal to the number of pain counters removed this way.