Cheapest priced copy (Fallout): $2.79 at Card Kingdom, near mint, their price list as of .
Alpha Deathclaw 
Creature — Lizard Mutant · 6/6 · Rare · Fallout · #336
Menace, trample
When this creature enters or becomes monstrous, destroy target permanent.
{5}{B}{G}: Monstrosity 4. (If this creature isn't monstrous, put four +1/+1 counters on it and it becomes monstrous.)
Legal inCommanderLegacyVintage
Not legal inBrawlStandardPioneerModernPauper
4 printings · $2.79 to $69.99 at Card Kingdom
3 rulings from Wizards of the Coast
- 8 March 2024Once a creature becomes monstrous, it can’t become monstrous again. If the creature is already monstrous when the monstrosity ability resolves, nothing happens.
- 8 March 2024Monstrous 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.
- 8 March 2024An ability that triggers when a creature becomes monstrous won’t trigger if that creature isn’t on the battlefield when its monstrosity ability resolves.