Call Up Emrakul to Help 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

Kicker (You may pay an additional as you cast this spell.) Exile target nonland permanent. Create a 1/1 colorless Eldrazi Scion creature token. It has "Sacrifice this creature: Add ." If Call Up Emrakul to Help was kicked, instead create a token that's a copy of Emrakul, the Promised End.