Like most Blitzs I get an early sheen.
I'm not 100% on his mechanics, but right now I was waffling between Crit chance, and Magic Penetration.
Guides floating around here aren't consistent.
Magic Pen is for AP blitzcrank, I recommend either armor pen for trinity force blitz or crit chance if you are building Infinity Edge after Sheen because power fist does straight up physical damage.
Generally I go Trinity force, then an Infinity Edge or Frozen heart (depending on the team).
Good to know Power fist works like that.
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