Prosperous Thief (J25) from Foundations Jumpstart, available at 401 Games Canada.

• Rarity: Uncommon
• Finish: Normal
• Artist: Fajareka Setiawan
• Card Text:
  Ninjutsu 1U (1U, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
  Whenever one or more Ninja or Rogue creatures you control deal combat damage to a player, create a Treasure token. (It's an artifact with "T, Sacrifice this artifact: Add one mana of any color.")