Advanced Floral Invocations 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

Landfall — Whenever a land you control enters, mill two cards. : Level 2 Whenever a land you control enters, creature cards in your graveyard perpetually get +1/+1. : Level 3 You may play lands and cast creature spells from your graveyard. If you cast a spell this way, that creature enters with a finality counter on it.