Cheapest priced copy (The List): $0.49 at Card Kingdom, near mint, their price list as of .
Yawgmoth's Agenda 
Enchantment · Rare · Invasion · #135
You can't cast more than one spell each turn.
You may play lands and cast spells from your graveyard.
If a card would be put into your graveyard from anywhere, exile it instead.
Legal inCommanderLegacyVintage
Not legal inBrawlStandardPioneerModernPauper
2 printings · $0.49 to $29.99 at Card Kingdom
3 rulings from Wizards of the Coast
- 4 October 2004The cards in your graveyard are not considered to be in your hand for any reason. For example, you can't discard them.
- 4 October 2004It will exile itself if it is going to the graveyard from the battlefield.
- 4 October 2004You count spells that were cast this turn before this card enters. (The Invasion FAQ is not correct on this point.)