Hi, I'm a pretty experienced Pyke player who wants to share some little hints with those who want to play Pyke. I can't say I'm the best Pyke player, but I can say that I know very well what I'm talking about. I saw on this site a lot of guides that are not so good so I decided to help the people here a little. I hope you like what I did here and that it will be useful just as it is for me.

Prowler's Claw - After using "Phantom Undertow" you can click on the ability of this item to pass through the enemy in case the distance is too long, or you can go through it to cause 15% more damage for a few seconds.

Duskblade of Draktharr - Due to the passive that gives more damage on a base attack and invisibility for a few seconds, it adds 5 more ability haste to the other legendary items and you can use the abilities faster when you need them to get out of bad situations or kill somewhat easier enemies. I prefer Prowler's Claw more than this one because it adds more lethality to the other items.

Mobility Boots - These are somewhat the perfect shoes for Pyke because you can roam midlane more easily and give you more mobility in case you are not attacked or attacking. Sometimes I prefer Ionian Boots of Lucidity, but the earlier ones remain basic.

Youmuu's Ghostblade - This item offers perfect mobility, damage and lethality.

Sanguine Blade - This item offers damage, lethality attack speed which is perfect for Pyke after finishing his combo, while the target he attacks is stunned, he can use his basic attacks faster to pass the maximum life he can execute with.

Edge of Night - This item is based on a lot of damage, because Pyke's passive converts the bonus life into attack damage, this item offers practically 73 damage in total plus lethality and a shield that blocks an ability once every 40 seconds.

Serpent's Fang - This item is exactly the same as Yoummu's Ghostblade except that it has only one passive which is obviously different. This item is especially good against targets that have a shield due to passive.

I tried to make these runes in such a way as to help you finish your job as soon as possible. Because Pyke relies more on abilities, I tried to inflict a little more lethality and attack damage after using the abilities. Why life as a "Defense"? Because at level 18 it reaches 90 HP which means 6 damage, a kind of third adaptive damage. Defensive runes don't make much sense to Pyke because he's an assassin, not a tank :)

If I forgot to add something or you didn't understand something from the build, don't forget to give me a PM or write in the comments. I hope I helped you! :D