Shroud of Kruphix

{x}{g}{u}, {t}: Draw up to X cards, then untap a
number of lands equal to X minus the number
of cards drawn this way.
Lands you control without counters on them have
"{t}: add {c}", and lands you control with counters
on them have "{t}: add one mana of any color".
When a land you control becomes tapped, if it
doesn't have a counter on it, put a +1/+1 counter
on it.