Cheapest priced copy (Tarkir: Dragonstorm Commander): $0.49 at Card Kingdom, near mint, their price list as of .
Protector of the Wastes 
Creature — Dragon · 5/5 · Rare · Tarkir: Dragonstorm Commander · #54
Flying
When this creature enters or becomes monstrous, exile up to two target artifacts and/or enchantments controlled by different players.
{4}{W}: Monstrosity 3. (If this creature isn't monstrous, put three +1/+1 counters on it and it becomes monstrous.)
Legal inCommanderLegacyVintage
Not legal inBrawlStandardPioneerModernPauper
2 printings · $0.49 to $0.79 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Tarkir: Dragonstorm Commander | 14 | Rare | $0.49 | — |
| Tarkir: Dragonstorm Commander | 54 | Rare | $0.79 | — |
2 rulings from Wizards of the Coast
- 4 April 2025Monstrous isn’t an ability that a creature has. It’s just something true about that creature. If the creature stops being a creature or loses its abilities, it will continue to be monstrous.
- 4 April 2025Once a creature becomes monstrous, it can’t become monstrous again. If the creature is already monstrous when the monstrosity ability resolves, nothing happens.