Okay, I need to write an original article about Nike Air Max Black. Let me start by understanding the user's requirements. The article should be between 600 to 900 words, use natural headings, and avoid unsupported claims. Also, I shouldn't mention that it's AI-generated. The user provided some context keywords: History Of, Nike Air Max 90 Black, Unboxing my new, and Nike Air Max. First, I should figure out the structure. Maybe start with an introduction about Nike Air Max in general, then dive into the history. The user mentioned "History Of" as a keyword, so that's important. Then, focus on the Air Max 90 in Black. Maybe talk about its design and features. The "Unboxing my new" part could be a section where I describe the experience of unboxing or purchasing the shoes. I need to make sure the headings are natural. Let me outline possible sections: Introduction, History of Nike Air Max, The Iconic Air Max 90 in Black, Design and Features, Unboxing Experience, and Conclusion. That seems logical. Wait, the user provided some context that includes "Nike Air Max 90 Black" multiple times. Maybe I should emphasize that model specifically. Also, I need to mention the history of the Air Max line, not just the 90. The Air Max was first introduced in 1987 with the Air Max 1, right? The Air Max 90 came later, in 1990. I should confirm the dates to be accurate. For the design and features section, I should talk about the visible Air unit, the color scheme of black, maybe the materials used like leather or mesh. Also, any technical aspects like cushioning and comfort. The user wants to avoid unsupported claims, so I should stick to known facts. For example, the Air Max 90 is known for its chunky design and visible Air unit. The unboxing section can be a bit more personal, but since the user wants the article to be natural, maybe frame it as a general experience rather than a personal story. Use the keyword "Unboxing my new" as a heading. Describe the packaging, first impressions, and initial feel of the shoe. I need to make sure the article flows well. Start with an engaging intro, then history, then focus on the specific model, design, unboxing, and wrap up. Check for keyword usage but not overdo it. Use variations of the keyword naturally. Also, check for any unsupported claims. For example, don't say it's the best shoe ever, just state facts. Mention Nike's innovation in Air technology, the cultural impact, maybe some notable collaborations or how the black color is a classic choice. Let me start drafting each section. Introduction: Hook the reader with the popularity of Nike Air Max. History: Talk about the evolution from Air Max 1 to Air Max 90. Design: Highlight the black variant's features. Unboxing: Describe the process. Conclusion: Summarize and maybe suggest where to buy or care tips. Need to ensure the word count. Let me estimate each section's length. Introduction and conclusion around 100 words each, history 150, design 200, unboxing 200. That totals around 750, which is within the range. Check for any repetition. The user provided the same keyword multiple times, but I should use it naturally. Maybe use "Nike Air Max" in the intro and history, then focus on "Air Max 90 Black" in the middle sections. Avoid markdown and use only the allowed tags. Use h2 and h3 for headings. Make sure the content is factual, like the release years, design elements, and features. I should also mention where the Air Max 90 fits in the lineup compared to other models like the Air Max 95 or 97, but maybe just a brief mention. Also, touch on why black is a popular color—versatility, style. Double-check the history: Air Max 1 in 1987, Air Max 90 in 1990. The 90s were a big time for sneakers, so the cultural context is important.