The Indomitable

• WOTC Official Reminder Textofficial rules
  Crew — Tap any number of creatures you control with total power N or greater: This Vehicle becomes an artifact creature until end of turn.

• WWizards of the Coast2023-11-10
  Official Ruling
  If The Indomitable is countered or dies after being cast from your graveyard, it returns to the graveyard. It may be cast this way again later.
• WWizards of the Coast2023-11-10
  Official Ruling
  Once you begin casting a spell from your graveyard, it immediately moves to the stack. Players can't take any actions until you've finished casting the spell.
• WWizards of the Coast2023-11-10
  Official Ruling
  You still pay The Indomitable's costs when casting it from your graveyard.
• WWizards of the Coast2023-11-10
  Official Ruling
  The casting permission granted by The Indomitable's last ability doesn't change when you may cast it from your graveyard.
• WWizards of the Coast2023-11-10
  Official Ruling
  The Indomitable checks if you control three or more tapped Pirates and/or Vehicles only as you begin to cast it. Once you begin to cast The Indomitable from your graveyard, it doesn't matter what happens to the tapped Pirates and/or Vehicles you control.
• WWizards of the Coast2023-11-10
  Official Ruling
  Only tapped Pirates and tapped Vehicles count toward the casting permission from The Indomitable's last ability.

Rulings via Scryfall