How does light shell work?

[I'll swallow your soul!]

After 30h I realized this skill is broken, it is supposed to negate damage or what? Had both upgrades to activate light shell when I dash and when I do tool/special, I clearly received damage any time it was activated, how does this powerup work?

[arguro]

Light Shell stops projectile damage only. It can be upgraded to reflect projectiles back at enemies for 40% of max health damage. This is a great upgrade to have against Karai and Bebop and Rocksteady. In the B&R fight, having Light Shell attached to your dash attack will basically kill Rocksteady without you having to even attack him. I just go after Bebop and Rocksteady will kill himself by shooting at my turtle and having the bullets reflect back at him. I think Light Shell is one of the best abilities in the game. You can pretty much ignore all projectiles by attaching it to your dash.

[thefollowingcharacters]

Light shell is an S tier ability in this game as it blocks all ranged projectiles. This makes many group fights easier, and feels mandatory to beating pact Karai your first time.