Eat to Extinction

• WOTC Official Reminder Textofficial rules
  Surveil — Look at the top N cards of your library. Put any number of them into your graveyard and the rest on top of your library in any order.

• WWizards of the Coast2020-01-24
  Official Ruling
  If you don't put the top card of your library into your graveyard, it remains on top of your library.
• WWizards of the Coast2020-01-24
  Official Ruling
  If the target creature or planeswalker is an illegal target by the time Eat to Extinction tries to resolve, the spell won't resolve. You won't look at or move the top card of your library.
• WWizards of the Coast2024-01-12
  Official Ruling
  You perform the actions stated on a card in sequence. For some spells and abilities, you'll surveil last. For others, you'll surveil and then perform other actions.

Rulings via Scryfall