Cheapest priced copy (New Phyrexia): $1.79 at Card Kingdom, near mint, their price list as of .
Omen Machine 
Artifact · Rare · New Phyrexia · #148
Players can't draw cards.
At the beginning of each player's draw step, that player exiles the top card of their library. If it's a land card, the player puts it onto the battlefield. Otherwise, the player casts it without paying its mana cost if able.
Legal inCommanderModernLegacyVintage
Not legal inBrawlStandardPioneerPauper
1 printing · $1.79 to $7.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| New Phyrexia | 148 | Rare | $1.79 | $7.99 |
2 rulings from Wizards of the Coast
- 1 June 2011Putting the land onto the battlefield or casting the card is not optional.
- 1 June 2011If the player is unable to put the land onto the battlefield (this is rare) or cast the spell (perhaps because there are no legal targets available) as the triggered ability of Omen Machine resolves, the card simply remains in exile.