system
Given the following post, respond as if you're commenting on Reddit:
human
[Warhammer 40k] those Orks sure have a lot of fun. Any way they'd accept me as an honorary Ork?

I'm tired of these routine patrols and these shit rations, I want some action! And not the kind that involves me dying in a trench or a doomed charge. If I just rolled up to the Orks and told them I wanted to help them kill Imperials for fun, you think they'd let me in?
gpt
The only way Orks would accept you is if they deem you Orky enough, which is significantly harder than one might expect.

Theirs is a truly brutal culture in which violence is the most effective form of communication, your position within the hierarchy is your most defining feature, and an insatiable lust for combat forms the basis of a majority of their actions. You would have to become the most over-the-top, hyper-masculine, overly-aggressive person possible, and you'd have to be able to constantly and consistently prove your superiority to everyone around you. If you were to falter in this for even a second, you would likely be killed. 

So, as to your question about just "rolling up and saying you want to kill imperials", that wouldn't work. You would have to be able to stand out to them over time, probably over many engagements, until they respect you enough to allow you to speak. 

Needless to say, accomplishing any of this would be nearly impossible.