Howlpack Piper // Wildsong Howler 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

This spell can't be countered. , : You may put a creature card from your hand onto the battlefield. If it's a Wolf or Werewolf, untap this creature. Activate only as a sorcery. Daybound (If a player casts no spells during their own turn, it becomes night next turn.) Whenever this creature enters or transforms into Wildsong Howler, look at the top six cards of your library. You may reveal a creature card from among them and put it into your hand. Put the rest on the bottom of your library in a random order. Nightbound (If a player casts at least two spells during their own turn, it becomes day next turn.)