Astro Vera shouldn't break the 20 health limit

@jasterrogue1 I agree with what @jaydabbler said, that's the whole point of the card. And trust me, +10 health is nothing when your opponent has 3 to 4 zombies with 5 or more attack.

Zombies have Undying Pharaoh and Planetary Gladiator as ways to absorb damage, and if you use them properly (cough cough, EscapeThroughTime, cough) you can easily absorb 10 or more damage.