Bellefray, The Midnight Wind

Presenting my idea for a possible Assassin/Jungle champion, Bellefray. Also, for context, she is half bat

[Q] "Iron Fangs" - Bellefray leaps to the target enemy unit within 410D, inflicting 10/25/40/55/70 (+130% AD) physical damage and applying on-hit effects. If the target is marked by Wings Of Change, this cooldown is refreshed by 2s. <Mana> 35/40/45/50/55 <CD> 8

[W] "Wings Of Change" - Bellefray whips up blade-like winds in a wide cone, inflicting 50/80/110/140/170 (+140% Bonus AD) magic damage and marking them for the next 5s. Bellefray gains 10/13/16/19/22% extra Lifesteal versus marked units. <Mana> 100 <CD> 16

[E] "Backdraft" - Bellefray's basic attacks passively steal 2/4/6/8/10 (+2.5% AD) health in bonus True Damage, which can stack up to 4 times. If Bellefray has 4 stacks on the target, her next basic attack consumes all stacks to inflict 7/8/9/10/11% (+1% per 60 AD) bonus physical damage and Stun them for 1s. Afterward, Bellefray cannot gain new stacks on the same target via indicator for a fixed 10s.

[R] "Banshee's Storm" - Bellefray unleashes a horrid screech, inflicting 175/250/325 (+200% Bonus AD) magic damage on all enemies within 450D and reducing their Attack Speed by 40% for 5s. If an enemy Champion is hit, Bellefray gains 40/55/70% Attack Speed for 5s on hit. <Mana> 150 <CD> 140/120/100

Ability "Silent Air" - If an enemy Champion is visible within 1000D of Bellefray while she is in brush, she becomes Stealthed indefinitely while out of combat, which is extended by 0.75s after leaving the brush. This has a 20s cooldown after leaving combat and cannot be used during combat.