DestroyThe only ways a permanent can be destroyed are as a result of an effect that uses the word “destroy” or as a result of the state-based actions that check for lethal damage (see rule 704.5g) or damage from a source with deathtouch (see rule 704.5h). If a permanent is put into its owner’s graveyard for any other reason, it hasn’t been “destroyed.”
A regeneration effect replaces a destruction event. See rule 701.19, “Regenerate.” (CR 701.8) target creature. If that creature
diesIs put into a graveyard from the battlefield. (CR 700.4) this way, its controller creates two tokens that are copies of that creature, except their power is half that creature's power and their toughness is half that creature's toughness. Round up each time.