Bio Zoids are a special type of Zoids released as part of the Genesis line and used in the Zoids: Genesis anime. All Bio Zoids are based on dinosaurs, are very skeletal in appearance. Most mass produced Bio Zoids like Bio Raptors, Raptor Guis, Triceras, Kentros, and some Megaraptors are being driven by robotic pilots which have souls of people trapped beneath them.
Hell Armor is a special organic armor used solely on the Bio Zoids. It is immune to energy weapons and can withstand most projectiles and edged weapons (save for those made of or utilizing Metal-Zi such as the Murasame Liger's blades, Lanstag's antlers/lance, and the missile-like weapons on Bamburian). Being organic it will dissolve when the Zoid it is attached to dies.
There are several versions:
Standard Hell Armor
This type of Hell Armor is the standard worn by the Bio-Raptors and most of the larger Bio-Zoids. It is the weakest form of Hell Armor.
Crimson Hell Armor
This is the armor used on the Bio Volcano. It is stronger than standard armor, capable of repelling more attacks.
Darkness Hell Armor
A near-impenetrable form of Hell Armour used on Bio Tyranno.