Life Return: Skeletal Prowess

Technique list name: Skeletal Prowess
Overview: Due to the effects of experimentation, Dagon can burn his calories in order to manipulate his skeleton, including his endoskeleton (bones), exoskeleton (shell), nails, teeth, and joints.
User: Dagon
History: Dagon created the first techniques trying to escape from a marine base, and developed the rest while on his adventures in order to protect himself and allies.
Techniques:


-level zero-

Name: Harden
Type: Life Return
Description: The user uses a combination of strength, endurance, and skill to harden the exoskeleton one level higher than it was before.
Effect: The skin is hardened to reduce damage by % equal to 1/2 strength and negate physical damage incapable of piercing the defined level. Max reduction of 50%
Requirements: .500 cal, X Strength, 30% skill, 20% endurance.

Name: Sharpen
Type: Life Return
Description: the user contorts the shape of one's bones to produce as many as 3 spikes per post. The spikes are as strong and sharp as the user's claws; if the user has no claws, iron.
Effect: Spikes can be produced as long as 1/2m
Stat Requirements: 250 .cal, 10% strength, 30% skill

Harden seems a little too much like tekkai or even a better version than tekkai. I realize that the way it's done is different as tekkai increases the durability while this is worded to reduce damage. However base tekkai only allows 60% boost to endurance (to match iron) like armor. This would easily surpass tekkai and costs less. At this point I can see this going two ways, it could boost endurance by the set limit of up to 50% or you could have it reduce damage by a small number for every 10% strength. So maybe 5% for every 10% of strength which would probably be limited by the 50% standard when the users strength reaches 100%.