Cheapest priced copy (Commander 2014): $0.99 at Card Kingdom, near mint, their price list as of .
Disciple of Bolas 
Creature — Human Wizard · 2/1 · Rare · Magic 2013 · #88
When this creature enters, sacrifice another creature. You gain X life and draw X cards, where X is that creature's power.
Legal inCommanderModernLegacyVintage
Not legal inBrawlStandardPioneerPauper
7 printings · $0.99 to $7.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Double Masters | 85 | Rare | $1.29 | $7.99 |
| Commander 2014 | 140 | Rare | $0.99 | — |
| Commander 2020 | 132 | Rare | $0.99 | — |
| Magic 2013 | 88 | Rare | $1.29 | $5.99 |
| New Capenna Commander | 247 | Rare | $0.99 | — |
| The List | NCC-247 | Rare | $1.29 | — |
| Tarkir: Dragonstorm Commander | 178 | Rare | $1.29 | — |
2 rulings from Wizards of the Coast
- 7 August 2020The creature's power as it last existed on the battlefield is the amount of life you gain and the number of cards you draw.
- 7 August 2020If you control at least one other creature when the ability resolves, you must sacrifice one. If you don't control any other creatures at that time, the ability won't do anything.