Blitzcrank

If he manages to grab you, wait until he uses his E BEFORE using yours to get away. If your adc gets grabbed, go stun their adc or Q him away from autoattacking your ADC.

Aftershock/Ancient coin recommended.

Braum

Harder than average.
Dodge his Q as much as you can. His wall can block your E, so keep that in mind.
Very tanky.
Relic Shield/Aftershock

Alistar

Hard engage. He can lock you down and rend you absolutely useless.
With some practice, you can dodge his W+Q combo with a quick E away from him. Done correctly, he will get stunned and you can pull him back into your team/turret as he has no abilities.
Relic Shield/Aftershock

Brand

Dodge his abilities as much as possible. Rush level 2 and all-in him to BURN his summs. NEVER E towards him if he has a stack on you and his Q is up. He will kill you.
Otherwise, easy matchup, squishy champion.
Electrocute/Ancient Coin

Ezreal

Has great range and is very safe. Boring matchup. Utilize bushes to zone.
Try to predict his Arcane Shift! Once it’s down, you can get an easy Stun on him.

Fiddlesticks

So. Annoying.
Can cancel your charging Q with his crows, will make you useless if he fears you, Health regen with his Drain and really strong Ultimate (ward bushes!)
Tip: when you are charging Q, wait for his E animation then throw your Q before the crows get to you.
RUSH LVL 2 AND ALL IN.
Will get Zhonyas, keep that in mind.
He is very squishy, so that's an advantage.

Evelynn

If you see this, you’re in for a bad time.
Get Maw.

Karma

Poke, Anti-Stealth, Shields+Speed boosts.
Hard matchup. Early game, she will poke your adc down very fast, and engaging against her is even worse.
Pick your moment to All-In very carefully.
Aftershock/Ancient coin OR relic (Depends on your adc: aggro=ancient coin, passive=relic)

Zilean

Literally has an Anti-Pyke kit.
AOE stun with a big range, a slow that’s almost as bad as Susan and revives an ally.
A good Zilean will wait at the very last second to ULT his ally so you don’t get a kill AND your ult goes on cooldown.
Extreme matchup late-game, but pre-6 is medium. Ask for ganks then.
Ancient Coin/Aftershock

Janna

Pretty easy matchup. Level 2 engage recommended. Beware of her ultimate (knockback and heal), can **** your E engage and your ultimate. Bait her let before using yours.

Use bushes.

Bard

Wards are extremely important. ward around the map so you can catch him when he's going for chimes.
You can grab him when he's in his portal.
Level 2 engage.

Leona

Ouch. Hard engage is very good against Pyke and Leona has it all.
Play safe, get Relic Shield.
Dodge her gap closer. If she hits you, spam the **** out of your E towards safety.

Lulu

Skill matchup.
Her polymorph is annoying, poke heavy. She can use her ultimate to counter yours.
Play around bush control.
DO NOT engage with E right away, she will polymorph you. Land your Bone Skewer first.

Lux

I am biased for this matchup. One of my most hated champions.
When she maxes her shield, I want to break my computer.
Play around bushes, be aggro when she misses her Q, punish her.

Relic Shield or Ancient coin are both good.

Morgana

Be sure to charge your Q for as long as possible, so you can bait her spell shield by targeting another enemy.

Nami

Honestly, this can go both ways. Her sustain in lane is amazing, so you shouldn't go for skirmishes. All-in or nothing. Deals very decent damage early game. Rushing level 2 and going all-in then is good.

Nautilus