tbh i don't play AP kog enough LOL, most of the times i play ad even in mid... I notice now and i need to overhaul the ap builds, for example stormsurge is so bad rn 😳😳
I remember being able to oneshot ranged minion with just dorans ring with E+R, but im not sure 100%.
When i was using the ap start was mostly against smolder buying guinsoo rush + seal. However i think in this meta u need to have a strong early game and both rushing guinsoo or leaving tome in your inventory don't help u in that imo, but seal with kraken is fine i think.

<3

I'm busy irl so i couldn't explain every item and it's strengths so I'll do a short explanation and after update the guide.
Riftmaker allow you to do long fights and the omnivamp is only an extra, imagine a situation where u're against 4 melle champions and your team can hold them well. so the value u get from runnan's + riftmaker get exponentially high, u get hp that is excellent for walking up, ap that scales in your entire kit and AH that isn't the worst stats.

About runnan's, if every auto u do applies the two bolts in an enemy, your damage output would be greater than other items, its 6% max health for auto because your W and it help a lot for getting lane priority in mid game.

Experimental Hexplate isn't the item you should do every game IMO it only works in some cases. For example, in my games i needed to build it only 2 times. Holding your R for fights don't have many drawbacks really unless if you need to check brushes so it fells really bad checking with Q or waiting for the team
Trinity force is a overall good item but i didn't get a chance to build it. Can work in strict cases when you really need the ms or want to be tank but not give any damage, really specific.

I do iceborn a lot and it's a good item when you need armor and see that you would get a great value for the slow. The key about this item its you don't need to use a skill + auto. U can auto and in the middle of the auto you use an skill and the iceborn will apply on that auto. There was a fight that i could apply it 4 times in a target using that, just AA + Q, AA + R and AA + E. It seams the 10% slow isn't a big o deal but if you can squeeze two autos in it, it's great.
BT tbh it's only when i feel u really need. The life steal applies on items on hit damage like wits end (don't apply on W sadly)
RFC works well with BORK against a poke comp that wont let u auto them easily

IMO rocketbelt is a underrated item for kogmaw, it boosts your damage and allow u to do really aggressive plays like ghost walking up and using it for dodge a varus R or Ashe ult for example.
It's a creative item and you don't need to use only forward dealing damage, imagine it as a vayne Q but as a item.

sorry if it's a lot of text, i did it in one shot and even before doing my lunch LOL

obrigado amigo

The major problem against cait isn't the DPS, is her poke. you have only 8 seconds to trade with her, if you manage to dodge cait EQ and run her down with Q + W you should win the trade but it isnt that easy because bot lane is a duo lane (or maybe it's easier). after bork just walk and kill because bork's slow.
The thing about statikk ins't beeing builded is because it only offer clear wave and a little damage. your main focus on kog is getting this 3 stats: HP, atack speed and resistances. Why theses three? Because they allow you to walk up into the enemy team and utilise W 100% efficient.
If you don't have health you cannot get in enemy team easily and need just play walking back (same for resistances) and atackspeed i think is easy to undestend.

It can work in some situations but i never tried in a real AD build.

and the on-hit stacks because it isn't a unique passive (i tested right now because idk when riot will fix this perfect game <3 )

Before they changed guinsoo pd was the best itens after guinsoo, but i tried it after the guinsoo nerf and did a spreadsheet(yes i spent like 3 hours in training mode) for some calculations, so I realise that its the lowest DPS in every scenario i tested.
about nashor's, the big problem i think it's because it only gives you brute damage, don't have utility like bork (slow + little sustain), runnan(spread your damage), titanic (clear wave + hp).
I think it can deal more damage than the others but in a real game the value decreases.

worth to mention i have a teory that if you can dodge every skill in a team fight, playing perfectly, building full damage is be best option(just an unrealistic opinion)

ty for the note <3. Tt is a long comment/ long guide and i realy need to practice my writing skills in english lmao

About conqueror, it ins't good because your AA only gives one stack. That means you need at lest 8 autos in order to stack full conqueror. Even if you get all stacks, kog`maw doesn't want a lot of brute ad because he has only one AD scale in his R.

About increasing passive damage, the itens that can do that are Draktharr's, Horizon Focus, Evenshroud's and navori. if think only navori and horizon focus can be builded but maybe it's not worth.
The other way to increase damage during passive is using a feature (bug), you can hit an enemy after dying and deal one more auto before exploding

i think braum is A tier rn, i mean he strugles a lot in some machups agaist ranged/disengage champions. There is a value but needs be in the right game. Its a solid lane in all states and realy good against lot of melle