Fizz is a highly underated AP burst mid character. Funnily enough, he is an excellent counter to most Ap Mids due to his high mobility and utility as well as quick burst damage. Though he may be played in the Jungle and Top Lane, his true potential is realised in the mid lane. The build I am presenting is a slightly tankier than usual fizz with the addition of a Rod of Ages however it doesn't refrain him from achieving 350-400+ Ap by the end of the game.
His runes are what I believe to be the standard for all my Ap mids who use mana and are relatively squishy. His quints give him 15 early game AP while his seals and glyphs give him sustainability in lane providing mana and magic resistance. This magic resistance does have an advantage over the first 20 minutes of the game. His marks are Magic Penetration just in case you meet someone like me who runs magic resistance runes, or to just create that extra damage through higher penetration.
My masteries are the standard 21-0-9 picking all AP in the offense tree and mana and movement speed in the utility tree. Not much more to explain there.
As people mature through the game, they realise that an instant dorans at the very start of the game is effective however holds them back movement speed wise which may cost them a kill, or a death. Therefore start with Tier 1 Boots and 3 Health Pots. Though I might have excluded it above, if you happen to get an early game kill and can afford it, be sure to buy a dorans ring for the durability. Once you are fed, creep wise or score wise, think about your next item. If you are facing a relatively strong damage team, build into a Rod of Ages, however if you are facing a team of squishies, go straight into a Rabadons Deathcap. Make sure that your next item is a Sheen, as that will have a great effect, especially with your higher AP. Afterwards, if you bought the Rod of Ages, build into that Rabadons Deathcap. After that, progress into a Lich Bane. This will give you great damage over time whilst your spells are on cooldown. Be sure to utilise this item fully by planting an auto-attack inbetween spells for max damage. After a Lich Bane, progress into a guardians angel. Not only will this provide you with more armour and hence survivability, but as the bursty AP mid you are, your team needs you in the fight as long as they can. Therefore a GA will bring you back twice, and make the enemy waste their time on you whilst your team goes to work on them. Finish off with a Will of the Ancients for more survivability and damage not only for you, but also your teammates. Also don't forget to consume elixirs if you have managed to finish your build.
When you think about it, two of Fizz's spells are utility, one of which has high damage and the other, low. The reason why I love to max his 'W' is because of its low cooldown and high damage. It is especially effective with your ignite where it leaves your enemy unable to heal properly due to the heal reduciton buff. Its also pretty cool when you walk away from them as they die from your 'W's damage. I then max his 'E' next, an amazingly useful utility which provides huge amounts of damage. This spell is the reason why he counters so many AP mids. It is effective against Morgana's ult, Karthus' ult, Galio's etc. However there is a glitch against Veigar's Event Horizon where if you try to jump through, you will remain untargettable, but will still be stunned. Finally max off your 'Q' which you should essentially use for approaching your enemy, or juking them. Obviously max your ultimate whenever you can.
Ignite and Flash, the basic spells for any carry. Ignite works a treat with Fizz's 'W' and it nearly cancels any healing throughout the duration. Flash is a must need spell at any level.
Farming and Early Game
One of Fizz's defaults is him being a melee character which leaves him vulnerable to ranged auto attack harass. However, if your enemy is able to do so, you should be able to use your 'Q' towards them whilst having activated your 'W'. If this has done enough damage, continue with your ignite and 'E' in order to have chance at finishing them off. If your 'Q' and 'W' don't do enough damage, then just escape via your 'E'. Obviously if you do this many times you will run out of mana so be sure to manage it effeciently. Farming shouldn't be a problem if you have intimidated your opponent by grabbing a few early kills however, as always, be aware of the jungler. Being melee pushes you down the lane a lot more. Its a good idea to use your 'W' when farming especially when you feel like you won't get the last hit off on time. Your jungler should give you his blue at around 7 minutes, therefore that is when you should start being aggresive with that 'Q' and 'W' combo.
Mid Game and Ganking
Mid game Fizz is probably where he excels above all. Your enemies, will be trying to finish off their early game items and hence have no Magic Resist (MR). After 20 minutes, be sure to start roaming the map and creating extra ganks in order to get yourself and your team fed. Fizz is a very quick ganker in combination with his 'E' and 'Q' which allows him to close out on his opponent. His best tool is his Ultimate "Chum the Waters", not only does this provide a slow and AOE effect, but also knocks your opponent up, allowing you to finish them off along with your team mates. Continue to farm as well as start taking responsibility for your team's buffs as they work effectively with Fizz's low CD.
Team Fights and Positioning
Fizz's Ultimate has a huge affect upon any team fight. Though it may not stun, it singles out one person, as well as slowing the immediate surrounding enemies. Do not necessarily use it as an engaging tool as it can, if used late, turn the tide (excuse the pun) of any team fight. Normally as fizz, you should be one of the first three people in a fight. Despite your squishyness, you can deal a lot of damage using purely your 'W' and 'Q' as well as Ignite. Then, once you feel like you are being targetted, use your 'E', causing slight confusion in the enemy team, providing a window for your teammates. Use your ultimate when you feel neccessary, then escape the fight, in order to recover from your cooldowns. If you have your Guardians Angel, be sure to remain in there until it is activated, then judge whether you should escape or keep fighting. A good Fizz player knows who to target and jumps straight to them in a team fight using his 'Q' or 'E'.
Fizz is a highly underated yet quite powerful champion. Though he can be played in the Jungle and Top lane, he excels brilliantly in the Mid Lane. He has a moderate mana usage and high burst damage and potential. He can be a devasting affect on a team fight through good targetting and effecient use of his ultimate. A guardians angel can sure turn a fight in his team's favour. But, to do well with him, you have to fish, to get something.