Jaspera Sentinel

• WWizards of the Coast2021-02-05
  Official Ruling
  You can tap any untapped creature you control, including one you haven’t controlled continuously since the beginning of your most recent turn, to pay the cost of Jaspera Sentinel’s activated ability. You must have controlled Jaspera Sentinel continuously since the beginning of your most recent turn, however.

Rulings via Scryfall