Cheapest priced copy (Oath of the Gatewatch): $0.79 at Card Kingdom, near mint, their price list as of .
Oath of Chandra 
Legendary Enchantment · Rare · Oath of the Gatewatch · #113
When Oath of Chandra enters, it deals 3 damage to target creature an opponent controls.
At the beginning of each end step, if a planeswalker entered the battlefield under your control this turn, Oath of Chandra deals 2 damage to each opponent.
Legal inCommanderPioneerModernLegacyVintage
Not legal inBrawlStandardPauper
2 printings · $0.79 to $0.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Oath of the Gatewatch | 113 | Rare | $0.79 | $0.99Out of stock |
| Oath of the Gatewatch Promos | 113s | Rare | — | $0.99 |
5 rulings from Wizards of the Coast
- 22 January 2016Each of the Oaths is legendary: if you control more than one of any particular Oath, you choose one to remain on the battlefield and the others are put into your graveyard.
- 22 January 2016Oath of Chandra’s last ability will trigger even if the planeswalker that entered the battlefield under your control is no longer on the battlefield, no longer under your control, or no longer a planeswalker. This is also true if Oath of Chandra wasn’t on the battlefield when the planeswalker entered.
- 22 January 2016The “legend rule” checks the full names of legendary permanents. You can control Oath of Gideon and Oath of Chandra at the same time, for example.
- 22 January 2016Even if you control a particular Oath, you can cast another of that Oath to take advantage of its enters-the-battlefield ability. It will enter the battlefield, causing its first ability to trigger. You will then choose one to keep, as detailed above, and then its enters-the-battlefield ability will resolve.
- 22 January 2016The last ability triggers only once per turn, even if more than one planeswalker entered the battlefield under your control.