Fenrakk were a species of arachnid-like Rahi with acidic saliva. The most well-known Fenrakk was enlarged by the Mask of Life and forcibly fused to Vezon in order for him to better guard the Mask. The Mask of Life also gave both Vezon and this Fenrakk the ability to absorb kinetic energy, allowing them to grow stronger with every physical attack made by them or against them. This ability made the two unaffected by all physical blows (as they immediately grow strong enough to withstand the attack), and the mask also granted them protection from other dangers such as lava.