If Aphelios is the Galaxy Brained Marksman, then Let's Create The Universe Brained Marksman

https://i.imgflip.com/3qb5l9.jpg

What concept would be smarter than Aphelios? I'll start.

So this champion has THREE abilities. You're going to have to stay with me for this one.

For their passive, this champion has a different passive for each combination of toggled abilities they have toggled and the passives change depending on the ratio of health to mana the champion has.

For their Q, W, and E they can switch between 5 different weapons PER ABILITY that each have their own stat bonuses. Every time a weapon is switched, that weapon's ability activates varying from a hook skill shot that increases in range by the amount of abilities used to a bubble shield that increases the amount of auto attacks you have by the ratio of projectiles the shield blocks.

You start with your ultimate ability and it is also a toggle BUT it cycles through classes rather than weapons. Thus the champion has the potential to be a tank that deals percent damage, a mage that deals magic damage with AD items, a bruiser, an assassin, and finally the default of marksman. And yes, each time you change form you activate that class' ultimate AND all of your abilities change their description similar to the Kayn forms.

Which brings me back to the passive. Depending on the combination of toggled abilities (including the ultimate), the champion will have one passive that is distinct from all other combinations that will have an effect ranging from increased movement speed that is increased by taking damage or health/mana regen based on the ratio of health to mana.

I call it...

https://i.imgflip.com/3qb89q.jpg

Hextechtimus Prime