Power-farming and late game scaling.
Burst damage and target access
Damaging a lot health champion inflicts adaptive damage and harvests a soul form the victim.
Gain a burst of Lethality and Magic Penetration after using a dash, leap, blink, teleport, or on leaving stealth.
Collect eyeballs for champion and ward takedowns. Gain permanent AD or AP, Adaptive for each eyeball plus bonus upon collection completion.
Unique champion takedowns grant permanent out of combat MS.
Improved attacks and sustained damage
Takedowns restore health and grant bonus gold.
Takedowns on enemies grant permanent Attack Speed.
+9% Attack Speed
+5 AD or 9 AP
Master Yi's ability to massively clear the jungle and power farm to build Dark Harvest stacks makes you a late game teamfight monster if you're able to get the reset.
Master Yi is able to easily proc the bonus Lethality from [Q] granting you even more kill pressure.
Eyeball Collection's snowballing damage potential means that if you're able to pick up a few early kills, you should be able to run away with the game.
The bonus Movement Speed from Relentless Hunter is fantastic for empowering your power farming playstyle with this setup, allowing you to clear quickly and get back out on the field after a recall.
Triumph's massive mid-fight heal after a kill means you'll be resetting and proccing your Dark Harvest stacks for a crazy amount of damage output.
Master Yi is a natural auto-attacker and the extra bit of Attack Speed from Alacrity means a faster clear for Dark Harvest stacks and massive teamfight damage.