Rune of Protection: Lands

{W}: The next time a land source of your choice would deal damage to you this turn, prevent that damage.
Cycling {2} ({2}, Discard this card: Draw a card.)

The List

Urza's Saga

oo
W Prevent all damage to you from a land source. (Treat further damage from that source normally.)
Cycling o2 (You may pay o2 and discard this card from your hand to draw a card. Play this ability as an instant.)

A source of damage is a permanent, a spell on the stack (including one that creates a permanent), or any object referred to by an object on the stack. A source doesn’t need to be capable of dealing damage to be a legal choice.

Can be used even when there is no damage to prevent. It prevents the next damage (if any) from the source this turn.