okay i didn't explain it very well and tbh i didn't understand it very well back then either:tad, you seem to misunderstand how it works. Rengar doesn't just 'get' ~4k worth of gold, lol.
once rengar and kha'zix hit level 16, they both gain a passive which states that they have to hunt the other one. if kha'zix dies while under this passive while rengar also has 14 stacks on his bonetooth necklace, the item is replaced with head of kha'zix which makes the stacks permanent
meanwhile if rengar dies, kha'zix gains a fourth evolution point.













