I've decided to post my own as well:
Kha'Sai (never said it had to be creative :P)
Lore
After finally killing and consuming Rengar, the Void had come to a realization: While other Voidborn only consumed to enhance the strengths they already had
(
), and others still only consumed to sate their curiosity (
), Kha'Zix was able to take the strength of others and combine it with his own. Knowing this, the Void decided to try something new: Allowing Kha'Zix to consume his brethren. The Void planted this idea in Kha'Zix's mind as if he himself had thought of it, and he zeroed in on his first target: Rek'Sai. After a gruesome battle that neither was sure they'd walk away from, Kha'Zix, covered in wounds that could've killed him, stood victorious. He quickly consumed Rek'Sai's corpse so regenerate himself, and once he was done, he felt the familiar rise of power that accompanied his evolutions. But this time it was different, he grew gargantuan in size and began to evolve in numerous ways at once. There was something else, too. His mind began to fill with memories that weren't his; he realized that his and Rek'Sai's minds were merging. He welcomed all of this without hesitation, recognizing it as the next stage of his evolution.
Description
Kha'Sai has the torso and legs of Kha'Zix and a tail resembling Rek'Sai's back half, minus her back legs. They have Rek'Sai's arms and Kha'Zix's arms (in their evolved form where his spike wracks would normally be, and look like the are 3/4 the size since the rest of him has grown. His spikes as they would appear when Kha'Zix has evolved them now protrude out of Kha'Sai's shoulders, pointing out to the sides. They have Kha'Zix's head, but Rek'Sai's face (including the blue armor), and a more elongated neck and the back end of Kha'Zix's head is pulled further back. Finally, Rek'Sai's dorsal fin protrudes from their back, right between their neck and the shell from which their wings protrude from. Imagine that all of the colors are the same, and that Kha'Zix isn't red, as he was when he killed Rengar.
Kit
Secondary Bar: Fury
Passive: Fury of the Xer'Sai
Dealing damage generates fury, up to 100. While Unburrowed, Fury will begin to decay back to 0. While burrowed, Kha'Sai can consume Fury to heal themselves, and if they unburrow before it is all consumed, what is left will be preserved.
Q: Weed Them Out/Prey Seeker
-Passive: Enemies who do not have allies within a certain radius of themselves become Isolated and are highlighted to Kha'Sai. The Isolation radius is only visible on enemy champions.
-Unburrowed Active: Kha'Sai gains three empowered basic attacks, causing them to spin around and deal damage in an area around them, as well as the target. If the target is Isolated, Weed Them Out becomes a point-and-click melee attack with both hands whose damage scales with the amount of fury they currently have.
-Burrowed Active: Kha'Sai sends out a pulse of void energy in a line in front of them, and shoot out two sets of spikes at 45 degree angles with the pulse of void energy simultaneously. The pulse goes farther and reveals enemies, but does less damage, while the spikes deal more damage, deal damage to those around the point of impact, and heal Kha'Sai if they are caught in the area of effect, but only reveal and apply a slow if the target is Isolated.
W: Burrow/Unburrow
-Passive: While burrowed, Kha'Sai gains Tremor sense, which allows them to see tremors of moving enemies, and they are able to differentiate between champions, minions, and monsters.
-Unburrowed Active: Kha'Sai burrows into the ground, severely reducing their sight range, but granting increased movement speed, new abilities, and healing from their passive.
-Burrowed Active: Kha'Sai comes out of the ground and regains their standard abilities and sight range, but losing the increased movement speed and healing, but preserving the remaining fury. If an enemy is within a certain range of Kha'Sai when they cast Unburrow, they will be knocked away from them. If an enemy is directly on top of Kha'Sai when they cast Unburrow, they will be knocked up.
E: Void Rush/Tunnel
-Passive: If Kha'Sai is involved in a kill, Void Rush's Cooldown is reset.
-Unburrowed Active: Kha'Sai leaps to a target area, dealing damage to all enemies they pass through and Area of Effect damage on impact. If Kha'Sai lands directly on top of an enemy champion, they will sink Kha'Zix's claws into the target, dealing damage and slowing them.
-Burrowed Active: Kha'Sai dashes in a target direction, leaving a tunnel in their wake. After a few seconds, tunnels can be re-entered and go on cooldown again. Tunnels eventually collapse, but can be destroyed when an enemy champion stands on a tunnel entrance.
R: Void Assault
-Unburrowed Active: Kha'Sai becomes invisible for a few seconds, gaining increased movement speed. When the invisibility ends, Kha'Sai turns red and it can be recast to go invisible a second time. At any point after the initial cast, Kha'Sai can enter a bush to extend the invisibility for a few seconds. This extra duration may be reset by entering other bushes. Once you enter a bush with Void Assault, that bush goes on cooldown, meaning that you cannot use it for the extended duration for a while. The reactivation timer acts independently, meaning that if you activate Void Assault and enter a bush, you get the extended duration, but Void Assault's initial duration may run out and the reactivation window may become open. The stealth will end either once Kha'Sai cannot find another bush in time, or after the second charge is exhausted, either through use or through letting it expire. Once the second use is exhausted, Kha'Sai will turn purple once again.
If anyone is wondering why I cut out evolution as part of the kit, I figured that Kha'Sai is so evolved and powerful already that any other evolutions would be overshadowed and not noticeable in comparison. Please don't feel like this is the golden standard or anything (again, lore is optional), just have fun with it!
