The Six Samurai - Zanji — Ruling

Regola generale

【About the『At the end of the Damage Step, if this card attacked: Destroy the monster this card attacked. You must control a face-up "Six Samurai" monster with a different name to activate and to resolve this effect』effect】
This effect is a Trigger Effect.
It's an effect that activates at the end of the Damage Step that this card attacked a monster, and that monster was not destroyed. (TL note: In the card's updated JP text in MD this is included in the effect's activation condition, avoiding any possible confusion about whether it's implied or not due to the nature of the effect.)
It's an effect that is activated and resolved if there is a face-up "Six Samurai" monster in your Monster Zone, except The Six Samurai - Zanji.
It will be activated in the Monster Zone if this card isn't destroyed by the battle, in the Graveyard if it's destroyed by the battle and sent there, or the banishment if it's destroyed by the battle and banished.
This effect does not target.

【About the『If this card would be destroyed, you can destroy another face-up "Six Samurai" monster you control instead』effect】
This effect is a Continuous Effect, which can be applied in the Monster Zone.
If this card would be destroyed by battle, decide if you will apply this effect during damage calculation, and destroy 1 face-up "Six Samurai" monster in your Monster Zone after damage calculation.
This effect can be applied even if this card would be destroyed by an effect during the Damage Step.
If both this card and another "Six Samurai" monster(s) in your Monster Zone would be destroyed at the same time, you cannot destroy that other "Six Samurai" monster(s) instead.