Cheapest priced copy (Duel Decks: Elspeth vs. Kiora): $0.99 at Card Kingdom, near mint, their price list as of .
Scourge of Fleets 
Creature — Kraken · 6/6 · Rare · Journey into Nyx · #51
When this creature enters, return each creature your opponents control with toughness X or less to its owner's hand, where X is the number of Islands you control.
Legal inCommanderPioneerModernLegacyVintage
Not legal inBrawlStandardPauper
5 printings · $0.99 to $2.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Commander Legends | 403 | Rare | $1.29 | — |
| Duel Decks: Elspeth vs. Kiora | 41 | Rare | $0.99 | — |
| Journey into Nyx | 51 | Rare | $0.99 | $2.49 |
| Journey into Nyx Promos | 51★ | Rare | — | $2.99 |
| Zendikar Rising Commander | 35 | Rare | $0.99 | — |
One ruling from Wizards of the Coast
- 26 April 2014The value of X is determined as the ability resolves.