Infernal Darkness

Enchantment, 2BB (4)
Cumulative upkeep-Pay {B} and 1 life. (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)
If a land is tapped for mana, it produces {B} instead of any other type.¹
"I thought the day had brought enough horrors for our ragged band, but the night was far worse." -Lucilde Fiksdotter, Leader of the Order of the White Shield
Illus. Phil Foglio

Crystal Keep Rulings Summaries

• All affected lands produce just one black mana regardless of how many it might normally generate. [Duelist Magazine #6, Page 131]
• Will remove restrictions on how mana generated by the land is used. [Duelist Magazine #6, Page 131] For example, the black mana from a Mishra's Workshop can be used for any purpose.
• The ability generates a replacement effect (see Rule 419). [DeLaney 1998/11/03]
• Note - Also see Cumulative Upkeep, Rule 502.13.

Format Legality	Legal in Vintage, Legacy Banned in Extended, Standard
Printings (1/6)	Ice Age (Rare)