A card many are bound to sleep on at first since it has alternatives, but if you have access to peak at the top card of the deck and these cards are available, they can save you a world of hurt for cheap. It's also a 0 cost card that is going to combo with anything that triggers once Defense events are played, so can be a cheap reliable way to get those triggers without thrashing your next turn like many other defense cards.
This card can also make defense abilities and cards that are looking for you to take no damage, like Unflappable, and make them a for sure bet. So for players, or even just hero decks, that have an dire need to play things on player phase and not burn their hand during the Villain phase, this is the card for you!