Okay, first off maybe I'm the only one who has realized this but currently with the June 9th patch normal damage armor has become almost obsolete. The only things I can think of that still do normal damage are Goblin's axe attack and the Lumbers arm swipe thingy. I don't mind the idea that enemies should have secondary attacks that allow them to do a different type of damage, such as a special ability that players would watch for and try to avoid, but simply changing monster attacks around to specific types will only make normal defense useless and cause game instability. Also the new Jelly spike ability is WAY too powerful. Ground spikes have always been hard to avoid and I just don't think it's a fitting ability for something soft, sweet and squishy to summon giant knight slaying thorns from the ground. But in all fairness I'd like to offer some suggestions for secondary attacks.
Jelly - Throws a small spike shaped blob at a knight that does Piercing Damage and summons a royal mini on impact
Wolver - Charges forward and jumps onto a knight biting them several times and causing Piercing Damage
Cromalisk - Changes the texture of it's skin to form spikes hurting anyone touching it with Piercing Damage
Scuttlebot - Self-Destructs causing small explosion and sending shrapnel in all directions that do heavy Elemental Damage
Everything does at least 20% normal damage. Just thought I'd mention.