Cheapest priced copy (Zendikar Rising): $0.35 at Card Kingdom, near mint, their price list as of .
Mind Drain 
Sorcery · Common · Zendikar Rising · #114
Target opponent discards two cards, mills a card, and loses 1 life. You gain 1 life. (To mill a card, a player puts the top card of their library into their graveyard.)
Legal inCommanderPioneerModernLegacyVintagePauper
Not legal inBrawlStandard
1 printing · $0.35 to $0.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Zendikar Rising | 114 | Common | $0.35 | $0.49 |
One ruling from Wizards of the Coast
- 25 September 2020If the target opponent can discard only one card or can’t discard any cards, they still mill a card and lose 1 life, and you gain 1 life.