PoE MrLeth builds

As the title says, I want a build that can one-shot legion. I came across this build, but I'm not sure if it's bait or not. Would this build be worth investing into, or should I look elsewhere? I assume it wouldn't make a big difference whether I have a mageblood or not.

Wanna try Ice shot, but couldn't find any builds. How trash is my first attempt at making a build? 1.3k hours and this is my first build.