When the echo triggered ability resolves, if you can't pay the echo cost or choose not to, you sacrifice that permanent
Flashback 3U
They contain enough packs to make opening exciting, but they also include accessories that make them useful beyond just pulling cards
What This Means for Buyers vs Resellers If you are a collector or player The gap is simply a better entry price
Youre gonna need a second removal spell, or a wall of chump blockers
Chaos Mystic Box X SPELL Quick-Play When your opponent activates a card or effect that targets another card(s) you control: Return 1 of your targeted cards to the hand (if face-down, reveal it), and if you do, destroy 1 card on the field, then you can Special Summon 1 monster from your hand that mentions "Light and Darkness Ritual" with a different name than the card returned to the hand, ignoring its Summoning conditions