Hello to everybody who is reading!
I'm probably not the best fizz around, but I seen some bad Fizz players last days because Fizz is at the F2P round right now, so I decided to make my very own first mobafire guide, I hope you like it.
If you think that anything wrong, that I missed something, or anything like that, you can leave a comment, I'll read that for sure!
[Created: 14/1/2015, Last changed: 14/11/2015]

Fizz is a very dangerous assassin, who can burst down full health targets, and get out alive very well.
His skills can allow you escape from sure death, or just chase down targets for sure death!
Fizz is a very strong assassin right now, because of his high mobility and his high burst damage which can instantly take down the enemy carries.
Also, he can dodge many skills like Karthus's Requiem, Orianna's Command: Shockwave, Brand's Pyroclasm, and many others.

When you picking Fizz, you basically risking the whole game.
Being behind with fizz kinda means being useless, so try picking Fizz only when you think that you can win the lane for sure.
Good times to pick Fizz:

• When the enemy picks squishy mage.
• When the enemy picks carries have no escape.
• When the enemy team don't have good peel.
• When your team have good engage champions.
• When Fizz isn't banned.
• When you want to.

Remember that you can't pick the same champion every single game, make sure you have other picks.

Pros: High burst damage. High mobility. Cute. Can dodge skillshots. Can gank bot/top well. GG if gets snowballed. Cute.

Cons: Hard to master. Squishy like most mid laners. Next to useless if behind. Melee. His ultimate travels slowly. Depends on his ultimate, unless fed.

Greater Mark of Magic Penetration Greater Seal of Armor Greater Glyph of Magic Resist Greater Quintessence of Ability Power

When to Use? Use it when playing blind pick/team builder, or simply if you don't have enough IP to buy runes and rune pages for custom matchups.

Stats: 7.8 Magic Penetration 9 Armor 12 Magic Resist 15 Ability Power

Greater Mark of Magic Penetration Greater Seal of Armor Greater Glyph of Scaling Magic Resist no one should read itOR Greater Glyph of Scaling Cooldown Reduction no one should read itOR Greater Glyph of Ability Power Greater Quintessence of Ability Power

When to Use? Use it when playing against a mid laner that deals physical damage(Zed, Talon, etc). Also, I'll recommend using the CDR glyphs over the MRglyphs. Note that if you picking the CDR glyphs, you need to make sure that you won't get over 40% with your in game build, since that would give you some wasted stats. An easy solution to this problem could be getting 6 CDR glyphs (Which gives 10% CDR at level 18) and 3 MR/AP glyphs, then not buying the CDR and just getting the magic pen boots instead.

Stats: 7.8 Magic Penetration 9 Armor 27 Magic Resist at 18 OR -15% Cooldown at 18 OR 10.7 Ability Power (from the glyphs) 15 Ability Power (from the quintessences)

Greater Mark of Magic Penetration Greater Seal of Health xFizzMaster18 OR Greater Seal of Scaling Health Greater Glyph of Magic Resist Greater Quintessence of Ability Power

When to Use? Use it when playing against a mid laner that deals magical damage(Anivia, Diana, etc). Also, I'll recommend using the scaling health seals over the flat health seals.

Stats: 7.8 Magic Penetration 72 Health OR 216 Health at 18 12 Magic Resist 15 Ability Power

Flash Flash is an escape as summoner spell, any champion should have that, no matter what skills he have and how he can escape with them, you must have that(well, maybe except Shaco). Never replace your Flash for no other spell.

Ignite Ignite is always a good spell to cast early as combo. also, you don't want to see the enemy flashing away and escaping with 10 hp, right?

Barrier Barrier can help you against hard burst champions like Zed, Talon, LeBlanc. the barrier will block a nice amount of damage that will increase your chance to survive.

Heal Heal is very similar to barrier, however it's not recommended since most mid laners have an ignite which counters heal, means you'll get a very low amount of heal.

Cleanse Cleanse isn't recommended too much, but it's an option if you are playing vs heavy crowd control team. after all, there is no Quicksilver Sash with AP stats, which is kinda bad. also don't forget that this can remove summoner spells debuffs like Exhaust or Ignite.

Exhaust Exhaust can help you even as a mid laner, since it reduces your target's armor and magic resist, slows him, and reduces his damage output by 40%. Also, a nice fact about this summoner spell is that it can used it both offensive and defensive ways.

Teleport Teleport can make sure you won't fall behind in lane, and even can help you to gank bot lane/top lane. Can be also used in the late game to make sure that you won't miss a crucial team fight just because the minion wave was pushing top lane and you recalled to defend it. you can take it against matches that are hard/almost impossible to win, to survive your early game without falling too behind, or you can just take it in general for some tp ganks or the late game team fights.

Use the build order in the beginning of the page. new season items came and I was too lazy to update this chapter right away, I'll try update it as soon as I can.

• Nimble Fighter is Fizz's passive.
• Fizz ignores unit collision, and takes reduced damage from basic attacks.

• The damage reduction occurs after armor reductions.
• The passive reduces damage taken by 4/6/8/10/12/14, and being upgraded when Fizz reaches level 1/4/7/10/13/16.
• The same unit collision effect can be obtained by having a Phantom Dancer or by activating Ghost.
• You won't get minion blocked like Dyrus got here.

• Urchin Strike is Fizz's Q.
• Range: 550
• Cost: 50/55/60/65/70 mana
• Cooldown: 10/9/8/7/6 seconds
• Fizz dashes a fixed distance towards the target enemy unit, dealing 10/25/40/55/70(+35% AP) magic damage, as well as 100% of his AD as physical damage, as well as applying on hit effects.

• Urchin Stike is a targeted dash ability, which can be dodged by simply and quickly moving once Fizz has cast the ability.
• Fizz will travel a set distance regardless of when he strikes his target.
• Urchin Strike applies all on hit effects(including life steal), making Lich Bane a strong pick on Fizz.
• Life Steal will be only applied to the physical damage, and not to the magical damage.
• Urchin Strike applies all spell effects as well, such as Rylai's Crystal Scepter Liandry's Torment, as well as spell vamp.
• Applied on hit effects, such as Lich Bane, won't benefit from either life steal or spell vamp.
• Spell shields will block the damage, but not the dash.
• Spell shields will block this ability.
• The physical damage can be dodged by Jax's Counter Strike, blocked by Pantheon's Aegis Protection, as well as by blind effects(such as Teemo's Blinding Dart, but magic damage is still being applied.
• While playing in the Crystal Scar(the dominion map), Urchin Strike's cooldown is increased by 1 second, reasulting in 11/10/9/8/7 seconds instead of 10/9/8/7/6 seconds.

• Seastone Trident is Fizz's W.
  
• Range: self-buff ability, no range.
• Cost: 40 mana
• Cooldown: 10 seconds
• Passive: Fizz's basic attacks rend his target, dealing 20/30/40/50/60(+45% AP)(+4%/5%/6%/7%/8% of the target's missing health) magic damage over 3 seconds.
• Active: For the next 6 seconds, Fizz's basic attacks deal bonus 10/15/20/25/30(+30% AP) magic damage.

• Both passive and active applying spell effects such as Rylai's Crystal Scepter Liandry's Torment, as well as spell vamp.
• Spell shields will not block this ability.
• Hitting the same target twice will not extand the passive duration, but will refresh it.
• Passive deals damage every half a second.

• Playful / Trickster is Fizz's E.
• Range: 400 for each dash, 800 total.
• Cost: 90/100/110/120/130 mana
• Cooldown: 16/14/12/10/8 seconds
• Fizz hops onto his trident towards the target location, becoming untargetable for a 0.75 seconds and gaining the ability to reactive the abilty for his second dash with no additional cost for a short time.
• If Fizz does not use his second dash, he splashes onto the ground below him, dealing 70/120/170/220/270(+75% AP) magic damage to nearby enemies as well as applying a 40%/45%/50%/55%/60% slow for 2 seconds.
• If Fizz does use his second dash, he still is splashes onto the ground below him, dealing the same magic damage, only this time in a smaller AOE range, and not applying a slow.

• Playful / Trickster has an AOE radius of 330 if used the dash once, but only 270 if used both dashes.
• This ability applies spell effects such as Rylai's Crystal Scepter Liandry's Torment, as well as spell vamp.
• Spell shields will block Playful/Trickster.
• Playful / Trickster does not break tethers like Fiddlesticks's Bountiful Harvest or Swain's Decrepify.
• Playful / Trickster can be used to jump over walls.
• Playful / Trickster can be used to avoid spells such as Karthus's Requiem or Caitlyn's Ace in the Hole.
• After Playful / Trickster is used, without activating the second dash, you can guide which direction Fizz will fall by right clicking before/as he drops for a longer reach (but same radius) on the slow/damage.
• Playful / Trickster cannot be used for half a second after using Urchin Strike.
• While playing in the Crystal Scar(the dominion map), Playful / Trickster's cooldown is increased, reasulting in 16/14.5/13/11.5/10 seconds instead of 16/14/12/10/8 seconds.

• Chum the Waters is Fizz's R.
• Range: 1275
• Cost: 100 mana
• Cooldown: 100/85/70 seconds
• Fizz throws a fish in a line that binds itself onto the first enemy champion it hits, slowing them for 1.5 seconds and increasing Fizz's magic damage against them by 20% for 6 seconds, excluding Chum the Waters's damage. A shark comes out from the earth to eat the fish after 1.5 seconds.
• If a champion has the fish attached to them, the shark knocks them up for 1 second. All other nearby enemies are knocked away instead. All enemies hit are dealt 200/325/450(+100% AP)magic damage and are slowed for 1.5 seconds afterwards.
• The fish provides true sight of its area of effect, and stays at the location it was thrown to until it binds to an enemy champion or is eaten.

• Chum the Waters is a collision linear skillshot that damages enemies in an area centered on the target.
• The slow is 50%/60%/70%.
• This ability applies spell effects such as Rylai's Crystal Scepter Liandry's Torment, as well as spell vamp.
• Spell shields will partially block Chum the Waters by causing the fish to drop to the ground instead of latching onto the target; however, the shark will still appear and deal damage around the fish after the normal delay.
• The fish will only attach itself to an enemy champion and will pass through all terrain and non-champion targets.
• If the fish is thrown onto a target without an active spell shield, the target will be slowed. If the spell shield activates while the fish is already latched on, the slow will remain but the shark's damage and knockup will be negated, consuming the shield.
• Chum the Waters initial slow can be removed by Cleanse and Gangplank's Remove Scurvy.
• Using Quicksilver Sash will remove the slow and will drop the fish into the ground as well.
• Both of the effects can hit stealthed units, and any stealthed unit hit by the fish will be revealed until the shark appears.
• Chum the Waters deals 1 true damage every 0.5 seconds as a countdown before the knockup, 6 true damage in total.
• Chum the Waters's secondary effect will activate immediately if it is attached to a champion and they die prior to the shark emerging.
• Chum the Waters grants sight around the fish, and reveals any target the fish is attached to.
• Chum the Waters shark damage will still deal damage to untargetable champions.
• This ability is considered to be a projectile for Braum's Unbreakable and Yasuo's Wind Wall.

Mainly, Fizz's combo is to hit someone with Chum the Waters, then jump on him with Playful / Trickster, Active Seastone Trident, auto attack him once, then Urchin Strike your target. at this point you can use Zhonya's Hourglass if need to.
The other option, when you start your combo with Urchin Strike instead of Playful / Trickster:
Hit someone with Chum the Waters, active Seastone Trident, then use Urchin Strike and use your Playful / Trickster to hit them OR escape if they is more there and the rest of you skills are enough to kill him. Remember that doing that without killing someone isn't worth it, so make sure you killing before using Playful / Trickster to escape.

Note: since patch 5.2 half of Urchin Strike's damage (both base and scale) were halved.
Also, Seastone Trident had some changes, For the most part, they swapped the active and passive, as well as removing the Grievous Wounds effects.
However, his ultimate, Chum the Waters got buffed, and now it's increasing Fizz's damage against it's target by 20% for 6 seconds. Means now Fizz is depends on his ultimate's damage more then ever, Try remembering that and play a bit more safe before you get level 6.
Second note: Patch 5.7 came and Seastone Trident got it's old effects once again, only this time it won't apply Grievous Wounds. This change greatly helps AP Fizz to be a bit stronger once again.

I made a Little video that shows what walls you can jump over with your Playful / Trickster.
You can watch it and train on a custom game to get better with Fizz's Playful / Trickster.
Don't forget you can use your Playful / Trickster to dodge tower shots or skillshots as well.
Also, a cool fact is that Fizz can smite while using Playful / Trickster, which can help you steal dragon/baron(well, if you have a smite).
Play Video

Centuries ago, an ancient water-dwelling race built a hidden city beneath a mountain in the sea. Though these creatures had their enemies, the city was an impenetrable fortress, and, in the safety it provided, they grew complacent. Fizz, however, harbored a curious spirit that could not be satisfied living so cushioned a life. Unable to resist the allure of danger, Fizz had a habit of sneaking out of the city to look for trouble. In his many adventures he grew to be a powerful fighter with a sharp cleverness that let him skirt danger with ease. One day Fizz returned to find the city abandoned: his people had vanished, leaving Fizz without a clue to explain their disappearance. With nothing left in the city to keep him, Fizz salvaged an enchanted seastone trident from the ruins and set out alone.

Fizz wandered the ocean in search of his people for years, using the skills he'd learned during his adventures as a young boy to survive. Finally, Fizz discovered the port of Bilgewater. He was fascinated with the existence of life above the water and could not resist exploring the island. In his endless curiosity, Fizz inadvertently meddled in the affairs of the humans who lived there, and his presence did not go unnoticed. His mischief angered many residents who eventually sought to capture or kill him. Fizz found himself cornered, and he prepared to return to the sea despite the fondness he'd come to hold for Bilgewater. As he stood at the docks, a massive dragon-shark attacked the port. Fizz defeated the beast, using his resourcefulness and knowledge of the creature's weaknesses to his advantage. Having earned the gratitude and respect of the humans, Fizz decided to stay in Bilgewater. To further serve his new home, he joined the League of Legends.

"Fizz makes even the saltiest sailors of Bilgewater look like drunken landlubbers in a fight. Good thing he's on our side."
― Miss Fortune, the Bounty Hunter

Well, that's it, my own very first mobafire guide.
Hope you learned something, and don't forget to have fun, because after all that's the reason for playing games :)
I would say more things but I have no idea what should I say.