Fervor
Enchantment
Creatures you control have haste. (They can attack and 
as soon as they come under your control.)
"We won't sit like lazy gob-slugs waiting for death to come to us. We'll bring death, shiny sharp, to our enemies." —Krenko, mob boss
Illustrated by
Magic 2013#129RareEnglishLegality
Rulings
Jul 1, 2012
If an attacking creature loses haste, perhaps because Fervor leaves the battlefield after attackers have been declared, it won’t be removed from combat.