Bicycle Elemental 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

As this creature enters, choose a word. Each card in your hand with the chosen word in its name, type line, and/or rules text has cycling . (, Discard that card: Draw a card.) Whenever you cycle a card, put a +1/+1 counter on this creature.