Cheapest priced copy (The Lost Caverns of Ixalan Commander): $4.99 at Card Kingdom, near mint, their price list as of .
Xolatoyac, the Smiling Flood 
Legendary Creature — Salamander Serpent · 6/6 · Mythic · The Lost Caverns of Ixalan Commander · #8
Whenever Xolatoyac enters or attacks, put a flood counter on target land. That land is an Island in addition to its other types for as long as it has a flood counter on it.
At the beginning of your end step, untap each permanent you control with a counter on it.
Legal inCommanderLegacyVintage
Not legal inBrawlStandardPioneerModernPauper
2 printings · $1.49 to $5.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| The Lost Caverns of Ixalan Commander | 8 | Mythic | $4.99 | $1.49 |
| The Lost Caverns of Ixalan Commander | 34 | Mythic | $5.99 | $5.99 |
2 rulings from Wizards of the Coast
- 10 November 2023The land stays an Island until the flood counter is removed, even if Xolatoyac, the Smiling Flood leaves the battlefield.
- 10 November 2023The land retains any land types and abilities it already had. An Island has the ability "{T}: Add {U}."