It'll usually buy you a turn from attacks and interaction, but discarding a card and skipping your draw step each turn is a steep cost to keep it around
Honorable Mentions In terms of non-foil, non-alternate art, new-to-the-game cards, those I mentioned above are the most valuable to open
Since Shadowheart, Dark Justiciar has this ability, we can choose a Background to go along with her
7 Restart - Mew ex Mew has had a very successful career in the TCG, with several top-tier cards printed in its name
If the creature had an ability defining its power and toughness, losing that ability will make it a 0/0
All that fun comes at a cost, and it's said if you can't afford to pay "you might find it hard to leave." Their leader, Jetmir, is a portly cat-person