Passive spell that returns % damage taken?

[DsD)Core(]

What's the best way to approach this? I only know of abilities that return a static amount of damage when the unit is attacked. I want a passive ability that returns 5, 10, 15, 20% damage taken on lvl 1, 2, 3, 4. Any spell or item ability that already does this? Like DotA's blademail? Or would I have to trigger this?

 

[Evan1993]

Kotg's passive, or crypt lords passive.

Thorns Aura or Spiked Carapace.

 

[Squishy]

Use Spiked Carapiece and modify to your needs.

EDIT: Beaten.

 

[Renendaru]

That would be thorns auras with levels?

EditL Wow... Beaten.

 

[DsD)Core(]

How blind of me.. Thanks guys.