Hello and welcome to my AP Mid Kog'Maw Guide.

Kog'Maw has strong poke, intense tank shredding and great sustain damage while maintaining a decent burst for AP too.

He's my favorite champ but I see that very few people play him and almost none know that he even has AP scaling. I decided to make this guide to give people a lead on what the heck to do since it's unlikely that information will be found in-game.

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Kog'Maw can go just about anywhere in his runes as far as most champs go. I prefer the Greater Glyph of Magic Resist glyphs for early game, Greater Seal of Armor seals for late game, Greater Mark of Attack Damage marks for early poke with W + farm, and Greater Quintessence of Ability Power for poke.

These are my suggestions so go through and figure out which you match with for each runetype to figure out what you need.


For marks you could go Greater Mark of Attack Speed, Greater Mark of Magic Penetration, or Greater Mark of Attack Damage. Atk spd gives the largest benefit late game while ad helps early game. M pen is nice but rarely have I ever needed to build pen on Kog'maw.

For glyphs, good options would be Greater Glyph of Scaling Magic Resist/ Greater Glyph of Magic Resist, Greater Glyph of Mana Regeneration or Greater Glyph of Mana. MR for defense if aggressive player and going to get into lots of trades, mana regen if going for sustain, and flat mana if you spam abilities too much (good for Kog'Maw noobies).

For seals I suggest Greater Seal of Scaling Armor or Greater Seal of Gold. armor for defense and gp/10 for farm boost if you can play his range well.

For quints go Greater Quintessence of Attack Damage, Greater Quintessence of Ability Power, Greater Quintessence of Movement Speed or Greater Quintessence of Spell Vamp. Ad for last hitting/ very early aggression. AP for better farm and poke with W. Spellvamp saves you from buying as many potions.

Kog'Maw's abilities can be maxed anyway really but I'll explain how I max them.

Max Void Ooze first for it's Push/Slow/Farm/Poke/Initiate(AKA just about Everything with 90% scaling). Then it's depending on the opponent whether to go Bio-Arcane Barrage or Caustic Spittle. If you're facing a strong early gamer go for Bio-Arcane Barrage and if you are facing someone with weak early game, get Caustic Spittle for the damage and atk spd.
If facing off against a tanky mid or a bruiser mid I recommend that Bio-Arcane Barrage is maxed first as it will do more damage for less against high health enemies.

Always Max Living Artillery as soon as you can because it allows you to easily push range limited champs out of lane extremely quickly while giving vision and amazing range, all for very little mana (unless it stacks). Still brings great damage and is worth spamming during direct conflicts.

For masteries with Kog'Maw I go 21/9/0

OFFENSE
tier 1 I do Fury for the attack speed but it's fine to do 2 atkspd and 2 into butcher for the last hitting
tier 2 I do Blast for the AP
tier 3 I do arcane knowledge for the pen and Havoc for more damage on everything
tier 4 I do Mental Force for the AP
tier 5 I do archmage for the AP
tier 6 I do executioner for the kill finishing because Kog'Maw has lots of range so you can easily get most of your kills from enemies running.

DEFENSE
tier 1 I do durability for the early health and vigor for that small sustain boost
tier 2 I do resistance
tier 3 I do for the early survivability

AP Kog'Maw takes a unique build.
There are 3 good starts I've found that I like.

Boots and two Health Potions - This I do for playing safe early. Mainly for champs with strong early game. EG: LeBlanc
Sapphire Crystal and two Health Potions - This is a strong one for lane sustain but also to poke and also lets you stay in lane longer. Good against sustain or high range mids. EG: Orianna
Amplifying Tome and a Health Potion - This gives you that extra power early game to try to knock people out of lane quickly. Good against champs with a weak early game. EG: Veigar

For the first back, what you buy depends on how you're doing.

Build into Sheen for more damage and slightly more damage
Build into Berserker's Greaves for safe play and more damage
Buy Needlessly Large Rod if you can afford it for ****-tons of damage
If you've got extra, buy a sight ward and a couple Health Potions or Mana Potions if you can

Once you've got Sheen you can go into Rabadon's Deathcap and then into Lich Bane.
If mobility isn't a problem then you can wait until after Deathcap or Lich Bane to get Greaves.

Up to you what you want here depending on gamestate.
Malady and Nashor's Tooth both increase Damage.
Rylai's Crystal Scepter give defense and Chase with w and r.
Guardian Angel for when you're not doing so well or against champs with strong gap closers.
Blade of the Ruined King for health sustain, attack speed and tank SLAUGHTER.

Jungle Ganks - If the jungle has strong initiate (like Maokai) then lay Void Ooze underneath the enemy once the jungle is in to slow as heavily as possible. Otherwise go around and lay Void Ooze across the lane to act as a wall giving the jungle a chance to get in and help.

Team fights - Just stay in back. Kog'Maw has outrageous range so remember to abuse that. Like Xerath you can play artillery with your Bio-Arcane Barrage and Living Artillery.

Blue buff and Red buff - Ask your jungle for permission and help if early game. Both benefit Kog'Maw greatly.

AP Kog'Maw has great farming power with Void Ooze and Living Artillery
For normal cs, basic attacks will suffice. If pushing is not a problem or a goal then lay void ooze down the entire minion wave and living artillery the caster minions while finishing the front minions with basic attacks to quickly finish entire waves.

Kog'Maw loves new friends and hopes to see you do well on the battlefields of the League of Legends!

Before downvoting just put in discussion your problem so I have a chance to fix/improve it.

Have Fun and don't forget to stop and nom the carries.