because of how rengars ult currently works it has an unfun use in combat, an up to 3 second delay of no attacking, no spells abel ot be used in order to use his ultimate, this makes hios ult have vurtually no use in a fight thatsalready started around him
here is my solution
rengars ultimate currently hasa 1 second base delay, which would give time to havea reactivate R effect
make reactivating R remove the delay, no longer provide ferocity passive gain or stealth, but give him the MS buff, 2-3 instant ferocity, and 1 stack of his passive that he has to use within 2 seconds and only has 1 use
this gives him an in combat use of his ultimate that is decent but not op because it's still a thrill because he can much more effectively stick ot a feeling target because he has the MS buff and 1 jump, while still beign a decent dps gain with the bonus ferocity that he will instantly gain
and at the same tiem it does not offer him a god mode damage (he doesnt get full ferocity after using the ferocity bonus and still ahs to rebuild some of it back), an ultimate escape (no get out of gan kfree cards), or a severly unfun aspect to play against (his mobility isnt insane because he only gets 1 jump, and being visable he can be effected by CCs and slows)
lastly, while rengar is stealthed i think he should also have vision of jungle mobs for better mobility when he does use that 3 second delay for escaping
remove the base 5 damage bonus, and make the leap range bonus one of the baseline effects (currently its a 9T effect)
replace the 9T bonus (which was the leap range bonus) with this
when rengar pounces a target it reveals them for 4 seconds
that is my idea for makign rengar more viable, and making his ult have an actual use when already in combat