Mardu Warshrieker

• WWizards of the Coast2014-09-20
  Official Ruling
  Mardu Warshrieker's raid ability isn't a mana ability even though it adds mana. It uses the stack and can be responded to.
• WWizards of the Coast2024-11-08
  Official Ruling
  Raid abilities care only that you attacked with a creature. It doesn't matter how many creatures you attacked with or which player, planeswalker, or battle those creatures attacked.
• WWizards of the Coast2024-11-08
  Official Ruling
  Raid abilities evaluate the entire turn to see if you attacked with a creature. That creature doesn't have to still be on the battlefield. Similarly, the player, planeswalker, or battle it attacked doesn't have to still be in the game or on the battlefield.

Rulings via Scryfall