Northern Wyvern

Flying
If {s} was played to cast Northern Wyvern, when Northern Wyvern enters the battlefield, choose
one:
•Grant Northern Wyvern "{r}: Northern
Wyvern gets +1/+0 until end of turn."
•Grant Northern Wyvern "Tap target creature.
That creature don't untap during their
controller's next untap step. Activate this ability
only once per turn."