Empichono is a colloquial and somewhat aggressive term, meaning "I get pissed off" or "I get angry." It's a strong expression of frustration or readiness to confront.
In the context of the song, Arcángel uses it to convey a sense of readiness for conflict. He says, "Pero, pero, si los saco, me empichono, me la engancho y me arrebato," implying that if he has to bring out his weapons, he will get angry and go all out. This word adds a raw, street-level intensity to his lyrics.
Arcángel's "Sin Embargo" is a bold declaration of his success and untouchable status in the music world. He wastes no time letting us know he's on top, even claiming, "No he empezado y ya cogió fuego el micrófono" [I haven't even started and the microphone is already on fire]. He sees himself as a king, constantly