Great damage for its cost, and some decks can take advantage of the Debris generation and make it an upside instead of a downside, at which point this card is obscene.
Upfront AoE with an unusual downside. Avoid by playing at the end of the fight or while your hand is full, or benefit from the debris with cards like Pillar of Creation or GUARDS!!!
Next turn, gain and . Retain your Hand this turn.
Gain 6 Block. Put a card from your Discard Pile on top of your Draw Pile.
Deal 21 damage to ALL enemies. Fill your Hand with Debris.
Deal 6 damage. Deals 2 additional damage for ALL your cards that have a cost.
Deal 7 damage to ALL enemies. All enemies lose 1 Strength this turn.
and 
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