This card should be SR or UR. Even the cost is just discarding 1 card is too good. In Addition, your monsters cannot be destroyed by battle in the turn you activate this card. Although, There is no description about "monsters" in the text
hallowed life barrier is a cheap Impenetrable Attack with a cost of a discard yet does both effects of impenetrable attack so i prefer it, cloning is a drop reward for kaiba i believe so i won't go for it with a ticket
this really should not prevent the destruction of monsters. nowhere on the text is that said or implied
Why? It works as intended. It didn't speficy what needs to be attacked (so it can be a monster or direct). It protects monsters because they can't be killed by 0 dmg (for example, you attacked with some high beater, they activate this, any dmg you would do with that monster is 0), it's normal ruling at work here.
Yeah, you really gotta pay attention to which cards discard others as a COST (Tribute to the Doomed) and which discard others as an EFFECT (Dragged Down into the Grave).
I feel like this is an underrated card. I don't know if it's due to the confusion of the ruling, or because it's not used a lot, but I've had more than a few duels where people honestly don't understand that it protects monsters for the whole turn, and will still try to attack me multiple times after I have used it. This card is a hidden gem in my Right Back at You deck.