Rhystic Cave
Land
Oracle Text
{T}: Choose a color. Add one mana of that color unless any player pays {1}. Activate only as an instant.
Watch Out
Mana abilities don't use the stackRules Note
If this card's activated ability produces mana and doesn't target, it's a mana ability. Mana abilities resolve immediately without using the stack — opponents can't respond to them. However, abilities that target (even if they produce mana) aren't mana abilities.