Grove of the Guardian
Land
: Add 
.
, , Tap two untapped creatures you control, Sacrifice this land: Create an 8/8 green and white Elemental creature token with vigilance.
Illustrated by
The List#GK1-124RareEnglishLegality
Rulings
Oct 1, 2012
To activate Grove of the Guardian’s second ability you can tap any two untapped creatures you control, including ones you haven’t controlled continuously since the beginning of your most recent turn.
Oct 1, 2012
You can’t tap Grove of the Guardian to activate both abilities at the same time.