Proposed Omen Kit [Previously cancelled champion]

Hi there, as some of you may know a long time back before Kha'zix they cancelled a champion called Omen. This was before my time, but he seems to be a cool champion and looked like this:

http://leagueoflegends.wikia.com/wiki/Omen

It was said that a good kit couldn't be made for him. Soooo... I thought it would be fun to make one. Here is how the proposted kit goes:

Type: Bruiser, assassin Lane: Jungle Style: 1 on 1 duelist

(not 100% on the stats but basically something like this)

HP - 600 - 2250 Range - Melee AD - 60 - 120 AS - .70 AR - 30 - 85 MR - 30 - 55 MS - 345 Regen - 10 - 27 Secondary bar - Mana (rage could work here too)

This kit is going to focus around a jungler who can catch people out and excels on dueling single opponents but is not as good in team fights. Like Kha'zix, they might be able to sneak in and take out a back line, but they will still die if they get caught in the middle of a team fight. I want to put an emphasis on his spiky look by essentially giving Omen quills that work like poison blow darts. In other words, the less evil version of teemo.

Passive - Xenobiology: If Omen doesn't attack or use an ability for 5 seconds he goes into camouflage mode where he becomes see through (the outlines would still be visible) making him harder to spot and not appear on the mini map. If he attacks from this mode his next basic attack deals an extra 75% of his AD. While camouflaged he moves slightly faster (basically a 5% when out of combat bonus). Taking damage will also break the effect.

Q - Spike javelin: 45 - 100 damage (+ 35% AD) (+10% of AP), CD 2 seconds - Omen fires off spikes from his back as a skill shot in a thin line. If he can hit someone they are slowed by 10% per spike hit up to 5 stacks (50%). Essentially this is Omen's opening move and he is highly rewarded for landing his spikes while also giving that feel of a porcupine'esque predator whose firing off quills into your opponent.

W - Digestive acid: 10 - 50 true damage burn over a 2 sec period on auto attacks, CD 10 sec - Adds a DOT true damage burn to Omens auto attacks. When active the acid burns away positive buffs from the target and reduces their healing. Also adds stacks of anti healing (25/50/75% less healing per stack). This makes omen an even better duelist on one target, but only if the fight is drawn out. So, good against other bruisers and tanks, not so good against late game adc's and burst mages/some assassins.

E - Tail sweep: 50 - 250 dmg (50% AP), knockback, CD 7 seconds - Omen sweeps his tail either to the left or right of himself knocking enemies back to prevent them from running. If the target is already slowed it applies another stack.

R - Chomp! (or proper biting ultimate): Ammo system, 3 shots, 100 damage (+50% AD, +50% AP), CD 160 seconds to 100 seconds at max rank - Omen makes a short dash toward the enemy champion (needs a target) and takes a bite out of them. For each added stack of slows the bite also does %hp dmg (up to 15% with all 5 stacks) and heals for the amount of acid stacks (like he's actually nomming them to death and getting health for the meal) (up to 25% of total damage dealt). If Omen kills a champion or jungle monster with Chomp the CD on it is halved (not reset). Chomp can only be used on champions and jungle monsters.

Where this champion excels - Really good at catching people out. Jump out of nowhere and take out people wandering river, going through JG, etc. However, he's not 100% invis so it's not an evelynn kill you even when you have wards kind of thing. He also has to hit his Q to be able to chase and if he uses Chomp early it doesn't do nearly as much damage. Also good at battling tanks. This kit wants a very drawn out fight (5-10 seconds or more) where they can build up stacks.

Where they are weak - Not too tanky, gets easily blown up if caught first, has no resistance to CC, must be able to actually catch opponent to win the fight.

Note: I considered having the W apply to the spike javelin but I thought that might be OP. A lot of the kit can look OP if you just look at raw stats but in actuality it's hybrid so doesn't scale hugely (base numbers are more important) and none of it works that well if they have to do a quick skirmish that only takes a few seconds. Omen also has no sustain unless he's using his ultimate, which gives him that crucial decision of whether to save it for a potential gank or use it up on monsters to make clearing the JG easier.

So, what do you all think? Too overtuned? Undertuned?

Ty for the feedback.

P.S. if Omen is a void monster make him purple and give him some extra armor and a third eye in his forehead. Cause... you know.. reasons.