Not Updated For Current Season
The masteries shown here are not yet updated for the current season, the guide author needs to set up the new masteries. As such, they will be different than the masteries you see in-game.
Pretty much this build counters tanks. The standard phage to slow your enemies, the madreds to give great attack speed and damage, the last whisper gives more attack speed, black cleaver is the damage item to make squishies even squishier and kill tanks faster, the banshees veil is there to block a random disable should it come your way. get this sooner if its really needed but generally youll want to go full out attack and only engage behind your tanks.
If you notice in masteries i put armor pen and and got the attack speed buff in the defensive tree. My runes, attack speed, armor penetration, dodge, and magic resist are complimented directly by me masteries. By the time you get your last whisper you should hve 2.3 attacks per second, drink a green elixir and that will max at 2.5 attacks per second. Kog maws 10% max health damage from his w + madreds hurts anyone he shoots especially with 2.5 attacks per second.
-Ignite can be useful, especially vs hp regen tanks/carries like nasus, mundo, shen, udyr,ezreal, etc.
-Exhaust is a good disable for you considering you have no disables, though youll tend too use this defensively due to its limited range
-Ghost can be useful for getting away and getting close and staying in range of your enemy while you proc phage on attack
-Flash not so useful in my honest opinion, maybe flash to your enemy and attack or flash to enemy before you die to get close with bomb
-Cleanse is good if you get blinded stunned etc, youll need every second to attack
-All other spells are okay i guess, but not kogs main skills
Level up bio arcane first. This will allow you to harass, kill neutrals faster, etc. Also your increased range will allow you to farm from long range if your in a disadvantaged situation. Second priority should be the caustic spit. Armor reduction is good, but the attack speed bonus is the main purpose of leveling this up. When the enemy champion decides to engage you strike them with q then batter them down with w, throwing in ignite and exhaust if you need to. If the enemy has heals of life drain use ignite in the beginning of the battle to cripple their healing and end it fast. If you think youll die, fight it out, if first blood is involved you get first blood if you suicide bomb them. If you are engaging the enemy try battering them from a distance with w r and e, only get close when your sure you can kill them.
In group fights dont use your w until you know you can shoot the enemy and keep that enemy in your shooting range. To get in this ideal position you can either stand next to your tank and scoot back as enemy approaches or you could approach from the back and shoot as the enemy team enagages yours. Your huge range will allow you many hits on their squishies. Great thing about kog is that if they are beefy, it doesnt matter, you will rip them up. Another great strategy is to sit on a ledge and fire from up there as your team fights. Fight to the end, kog maw only runs when theres no fight involved.
Kog is okay at destroying towers, no where near as great as kayle, but he can fire from long range and quickly disengage if the creep wave dies or if you sense an enemy incoming. If you think you cant run, let the tower kill you before the enemy can get to you, then use that bomb on the enemy minion wave for some money.
This skill does "true damage" so it bypasses resistance and armor. Use it on ANYONE nearby at low hp, its worth a try. If no ones at low hp or you know you cant catch up to the enemy, use it on a creepwave.