Without looking up damage, I guess the *result* of lethal damage is a "destroy" effect... a spell like Beast Within "bypasses" the damage part and goes directly to the "destroy" result.... so I'll continue on and we can always back up if you have more questionsFrom the Comprehensive Rules (August 23, 2019—Commander 2019)
- 701.7. Destroy
- 701.7a To destroy a permanent, move it from the battlefield to its owner’s graveyard.
- 701.7b The 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.”
- 701.7c A regeneration effect replaces a destruction event. See rule 701.14, “Regenerate.”