When Natural Emergence enters, return a red or green enchantment you control to its owner's hand. Lands you control are 2/2 creatures with first strike. They're still lands.
2004-10-04
You choose the enchantment to return on resolution of the triggered ability. This is not targeted.
2009-10-01
A noncreature permanent that turns into a creature is subject to the "summoning sickness" rule: It can only attack, and its {T} abilities can only be activated, if its controller has continuously controlled that permanent since the beginning of their most recent turn.