Kallista's current state.

So Kallista has been trash since season 6 and we are now in preseason 7 with still no hope of her getting any better due to all of the shields in the game and what not you are gonna miss your rend and her lack of damage early game makes her laning phase unbearable. I have an idea though. What would happen if her Rend did true damage if the enemy champ was below say 20 or 15% health but it needed a certain amount of stacks to create the true damage. It would maybe not be broken but would require good use of the stacking of her spears and timing to get it right it could help. I don't know it was a shower thought.