Cheapest priced copy (Kamigawa: Neon Dynasty): $0.35 at Card Kingdom, near mint, their price list as of .
Mirrorshell Crab 
Artifact Creature — Crab · 5/7 · Common · Kamigawa: Neon Dynasty · #63
Ward {3} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {3}.)
Channel — {2}{U}, Discard this card: Counter target spell or ability unless its controller pays {3}.
Legal inCommanderPioneerModernLegacyVintagePauper
Not legal inBrawlStandard
2 printings · $0.35 to $0.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Kamigawa: Neon Dynasty | 63 | Common | $0.35 | $0.99 |
| The List | NEO-63 | Common | — | — |
3 rulings from Wizards of the Coast
- 18 February 2022If a channel ability requires a target, you may not activate it without a target just to discard the card.
- 18 February 2022Discarding the card is part of the cost to activate a channel ability.
- 18 February 2022If a player casts a spell that targets multiple permanents their opponent controls with ward, each of those ward abilities will trigger. If that player doesn't pay for all of them, the spell will be countered.