Shiko, Paragon of the Way

• WOTC Official Reminder Textofficial rules
  Vigilance — Attacking doesn't cause this creature to tap.

• WWizards of the Coast2025-04-04
  Official Ruling
  A resolving copy of a permanent spell becomes a token. That token isn’t “created” and won’t interact with abilities that care about tokens being created.
• WWizards of the Coast2025-04-04
  Official Ruling
  If a spell has in its mana cost, you must choose 0 as the value of X when casting it without paying its mana cost.
• WWizards of the Coast2025-04-04
  Official Ruling
  If you don’t want to cast the copy, you can choose not to; the copy ceases to exist the next time state-based actions are checked.
• WWizards of the Coast2025-04-04
  Official Ruling
  If you cast a spell “without paying its mana cost,” you can’t choose to cast it for any alternative costs. You can, however, pay additional costs, such as kicker costs. If the spell has any mandatory additional costs, those must be paid to cast the spell.
• WWizards of the Coast2025-04-04
  Official Ruling
  You cast the copy while Shiko’s last ability is resolving and still on the stack. You can’t wait to cast it later in the turn.
• WWizards of the Coast2025-04-04
  Official Ruling
  If the spell you cast has in its mana cost, you must choose 0 as the value of X when casting it without paying its mana cost.

Rulings via Scryfall