Kha'Zix evolutions

why kha can not obtain the fourth evolution? because it would change its influence in the games? actually yet there is a way to get the fourth evolution, Therefore the presence in a game of a kha'zix completely evolved is possible, and in some games is real. So why the chances of this happening must be dependent on the presence and satisfaction of conditions totally independent of the player who play kha'zix? "The Hunt is on" how it works? kha must be at LV16, rengar must have 12 stacks, both in the same game and in different teams. And now where it is supposed to be the challenge 1v1? when is a game 5v5? no matter which one you are, the result of the Hunt will depend very much on how it is going the game between the two teams with all the different randomness that may occur. -if rengar wins gets complete stack, plus a bit of vision more in the brush. -if kha wins gets the fourth evolution

and now: -if rengar loses still has the opportunity to earn and get stack to 20 as in every game, will not have an increase of vision, oh well. -if kha loses will have no hope of having all four the evolution to the next game in which will have rengar as opponent

So is okay or not that kha reaches the fourth evolution? if not, then why is there a way to get it? if so why it is not possible in every game? instead only if you meet the conditions extremely rare?

I think kha should have the possibility to reach the fourth evolution in every game, as well as in every game can rengar reach 20 stacks. I personally find "The Hunt is on" quests useless and would remove it.

about how to get to the fourth evolution to kha'zix might give it to him when he reaches lv18, or after he kill (And devoure/Consume, since that is what is said he should be suosed to do) each one of the 5 champions of enemy team .. I do not know, put together with the conditions that you want but please do so as to allow kha reach the four evolutionsin every game and not just when it is against rengar (and only when manages to kill him)