If the target creature is an illegal target as Hydaelyn, the Mothercrystal's last ability tries to resolve, it won't resolve and none of its effects will happen
This can beat up players itself pretty well, but it also works well with a wider board by allowing you to keep up some defenses after an attack with a bunch of vigilance creatures
Notable Cards: Aurora Dreaming Guardian Grab Your Sword Where to buy: 6
Players can respond to a spell that will give you your tenth permanent, but they can't respond to you getting the city's blessing once you control that tenth permanent
First, you need to survive long enough to be able to cast two spells in one turn cycle
Overall, I wouldnt overload on these anti-lifegain cards as if you feel like you need to, then you probably shouldnt be playing a red deck in that metagame