Cheapest priced copy (Shards of Alara): $0.99 at Card Kingdom, near mint, out of stock, their price list as of .
Where Ancients Tread 
Enchantment · Rare · Shards of Alara · #122
Whenever a creature you control with power 5 or greater enters, you may have this enchantment deal 5 damage to any target.
Legal inCommanderModernLegacyVintage
Not legal inBrawlStandardPioneerPauper
2 printings · $0.99 to $6.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Shards of Alara | 122 | Rare | $0.99Out of stock | $6.99Out of stock |
| Commander 2013 | 130 | Rare | $1.29 | — |
One ruling from Wizards of the Coast
- 1 October 2008The ability checks that creature's power only once: when that creature enters. The trigger checks a creature's initial power upon being put on the battlefield, so it will take into account counters that it enters with and static abilities that may give it a continuous power boost once it's on the battlefield (such as the one on Glorious Anthem). After the creature is already on the battlefield, boosting its power with a spell (such as Giant Growth), activated ability, or triggered ability won't allow this ability to trigger; it's too late by then. Once the ability triggers, it will resolve no matter what the creature's power may become while the ability is on the stack.