Aside from what DEWO posted I'd like to add that in most cases you don't need the lizard buff as much as the golem buff. If you were to say go for any buff it'd be that one.

another thing is that malady isn't a bad weapon but for WW there are far better ones such as BLOODRAZOR! (as DEWO already pointed out) and one of my absolute favorites that if your so intent on Lifesteal and your Ult than why not get Bloodthirster? 100 Attack Damage, 25 Life Steal. Passive: Gain an additional 1 Physical Damage and 0.25% Lifesteal per kill. Maximum of +40 Damage and 10% Lifesteal. Bonuses are lost upon death.!!!

I'm not trying to flame your *** but i'd just recommend updating your guide taking in some of our suggestions for example.

another WW guide for breakfast!

Ok @ Chulupa, this is a laning WW guide as far as i see so no smite needed... but neither is ignite.
You go with smite for lvl 1 jungling.

buuut:
If you carry that much about lizard buff... than your mastery tree is a bit ****ed imho...

Phantom dancer is totaly unessesary item. TBH you dont need the AS since your HC will keep that up. You dont need dodge since you have TONS of lifesteal from HS.

And sunfire cape... worst idea ever... srsly.
Your ultimate stuns for 1.6s = about 80 damage. There are better items for that...

NO BLOODRAZOR? on WW?
that makes your statement:
"When u get all ur dps items using ur ulti after strike deals Massive dammage(like 3/4 to low healthed char)"
A very wrong statement. With those items, you will do exactly 540 physical damage (and i still dont count Armor reduction) and 80 damage from your cape (not counting Magic resist reduction) making it a total of 620 damage.
Lest look at the most squishy target Soraka.
At lvl 18 she has 1629HP (Without ANY item) hmm. So not counting MR and Armor you will take only 38% of her HP... and that is still counting that she will not heal, she will be dumb and not buy any items and that she has 0 MR and Armor.
Remember that you will stack the black cleaver while your ulti, you wont get all stacks instantly, so we cant neglet armor.
Where did you make your calculations??? did you made ANY AT ALL?

this isnt a bad build though u just need some work on this build

why jungle without smite? u should just jungle in the beginning with smite.
i dont think u should get ignite though. u should get madreds bloodrazors