Cheapest priced copy (March of the Machine Commander): $0.59 at Card Kingdom, near mint, their price list as of .
Abzan Battle Priest 
Creature — Human Cleric · 3/2 · Uncommon · Khans of Tarkir · #1
Outlast {W} ({W}, {T}: Put a +1/+1 counter on this creature. Outlast only as a sorcery.)
Each creature you control with a +1/+1 counter on it has lifelink.
Legal inCommanderPioneerModernLegacyVintage
Not legal inBrawlStandardPauper
4 printings · $0.59 to $3.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Iconic Masters | 2 | Uncommon | $0.69 | $2.99 |
| Khans of Tarkir | 1 | Uncommon | $0.69 | $3.49 |
| March of the Machine Commander | 164 | Uncommon | $0.59 | — |
| The List | KTK-1 | Uncommon | $0.59 | — |
2 rulings from Wizards of the Coast
- 20 September 2014The cost to activate a creature's outlast ability includes the tap symbol ({T}). A creature's outlast ability can't be activated unless that creature has been under your control continuously since the beginning of your turn.
- 20 September 2014Several creatures with outlast also grant an ability to creatures you control with +1/+1 counters on them, including themselves. These counters could come from an outlast ability, but any +1/+1 counter on the creature will count.