[Champion Concept] Void Symbiote

This is a concept I've been had for a while, it's a champion that would work as a mage, support or even replacement for an ADC in the bot lane.

Range: 550 Resource: Mana

Passive: Basic attacks, including on hit effects, deal entirely magic damage instead of physical damage(100%AD, 20% AP), in addition these attacks cannot crit, instead void symbiote will deal additional true damage equal to 1% of total pre-mitigation damage for every 5% of crit chance, for a maximum of 20%

Q: Void Shard: fires a projectile in a line, dealing damage to all enemies hit and stealing 15/17.5/20/22.5/25% movement speed from any champions hit, gaining attack speed equal to the stolen movement speed, host allies also receive this bonus

W: Infest: Reaches forward in a line skill shot, latching on to the first champion hit and attaching to them, enemies take damage over time and are released after 6 seconds, when attached to an ally both void parasite and the host ally gain increased healing for the duration, Melee allies gain additional range for a total of 500 but can only apply on hit effects within their original range. Reactivating will detach from the host. Can auto attack freely while linked to an ally.

E: cast range:200, targeted, blocks one auto attack and any associated on hit effects, dashing backwards equal to the distance of the host ally's auto attack or 550 if no host, enemies hit are staggered, taking extra damage from the next basic attack or ability that hits them from any source within 1.5 seconds, using any movement abilities such as blinks or dashes will cause staggered enemies to be rooted for 2 seconds but will not stop the movement effects of the ability.

R: Ethereal: Void Symbiote and a host ally become untargetable and gain increased movement speed for a short time, During this time both champions are ghosted and cannot deal damage, the host ally can still use abilities but any damaging effects will be ignored. Reactivating the ability will end the effect early

That's the basic idea of the kit, I'll probably add to it and change it a bit over the ext little while.