Does {Bloodlord of Vaasgoth} Last ability proc if {Cairn Wanderer} Enter giving it 3 counters?
{cairn wanderer} is every creature type at ANY time, so this is also a vampire spell as you cast it. It will gain bloodthirst 3.
EDIT: ruling
702.72a (http://imtgapp.com/forum/index.php?action=imtg;area=rule;number=702.72a): Changeling is a characteristic-defining ability. "Changeling" means "This object is every creature type." This ability works everywhere, even outside the game. See rule 604.3.