This card’s effect activates in the Graveyard. If “Destiny Hero – Double Dude” is removed from play its effect will not activate.
If “Destiny Hero – Double Dude” is destroyed and sent to the Graveyard while in the hand or Deck his effect still activates, and you can Special Summon the 2 “Double Dude Tokens”. He could be destroyed in the hand or Deck by effects like “Neo-Spacian Aqua Dolphin” or “Chain Destruction”.