Learn Japanese with Anime - I’m Gonna Be King Of The Pirates! (One Piece)

Analysis

海賊王 (noun) means “pirate king”. The kanji of 海賊 literally means “sea thief” which is “pirate” and 王 means “king”.

Noun に (particle) なる (verb) means “to become something”, so 海賊王になる means “to become pirate king”.

俺 (pronoun) means “I” or “me” used by men in a rough and manly way and the は particle indicates the topic of the sentence.

So 海賊王に俺はなる means “I will become pirate king”.

Now, let’s look at the word order in this sentence.

The target (海賊王に) comes first, followed by the topic (俺は), and the verb (なる) in the end.

In Japanese, a sentence basically begins with a topic (俺は) and ends with a verb (なる). And a target (海賊王に) or direct object usually comes right before the verb. So in the usual order, it will be 俺は海賊王になる.

But it sounds normal and monotonous which is not so influential. To make it more influential, you can change the word order. This method is often used when you want to emphasise and leave an impression on listeners, such as poems, lyrics, advertising slogans, and strong declarations.

Also, the dictionary form of a verb without sentence ending particles is often used when you simply determine or declare that you will do something in casual speech.

So this sentence is influential and declarative which leaves a strong impression on listeners.