Scaretiller

• WWizards of the Coast2019-08-23
  Official Ruling
  Scaretiller's ability is a triggered ability, not an activated ability. It doesn't allow you to tap it whenever you want; rather, you need some other way of tapping it, such as by attacking.
• WWizards of the Coast2019-08-23
  Official Ruling
  If Scaretiller becomes tapped while casting a spell or activating an ability, that spell or ability resolves after Scaretiller's triggered ability has resolved.
• WWizards of the Coast2019-08-23
  Official Ruling
  Neither mode of Scaretiller's ability counts as playing a land. It can put a land card onto the battlefield even if you've already played your land for the turn, and even if it's not your turn.

Rulings via Scryfall