Okay, so I need to write an article about Diego Costa's Chelsea celebration. Let me start by understanding the requirements. The user provided some context points: "Deadly, savage," mentions of 58 goals and 120 appearances over three and a half years, Diego Costa celebrating Chelsea's [something], Antonio Conte's insane [maybe tactics?], and three instances of "Chelsea." The article should be 600-900 words with natural headings, avoid unsupported claims, and not mention it's AI-generated. First, I need to structure the article. Maybe start with an introduction about Diego Costa at Chelsea. Then talk about his career there, his goals, appearances. Then his celebrations, maybe how he was a key player under Conte. The "savage" and "deadly" terms might refer to his playing style or his celebrations. The user mentioned "Diego Costa celebrating Chelsea's" so maybe specific celebrations after important matches. Also, Antonio Conte's role is important here, perhaps how his tactics or system helped Costa. I should check if there are any well-known celebrations by Costa. Maybe his goal against Manchester United in 2015? Or after a significant win. I need to make sure the facts are accurate. 58 goals in 120 appearances—need to verify that. Also, three and a half years at Stamford Bridge. Maybe from 2014 to 2017? He left in 2017, so that fits. Natural headings: Maybe "Diego Costa's Rise at Chelsea," "Deadly Finishing and Savage Attacking Style," "Iconic Celebrations Under Antonio Conte," "Legacy and Departure." Need to connect each section with the context points. Avoid unsupported claims: So no making up stats or quotes. Use the provided info and maybe some general knowledge about his time at Chelsea. Ensure that when mentioning Conte, it's about his tactics or system that utilized Costa's strengths. Check for the exact number of goals and appearances. Let me confirm: Diego Costa played for Chelsea from 2014 to 2017, so three and a half years. Goals: 58 in 120 apps. Yes, that's correct. Celebrations: He had a signature celebration where he would mimic a gunshot with his hand, which became popular. Maybe mention that. Also, when Chelsea won the Premier League in 2014-15 under Mourinho, but he was part of that team. Then under Conte in 2016-17, they won the Premier League again. Maybe his celebrations after those wins. Need to make sure to use the keywords naturally, like "Diego Costa Chelsea celebration" in headings and throughout the text. Also, the user mentioned "Chelsea" three times in the context, but maybe they just want it to be part of the article naturally. Start with an introduction paragraph about his impact. Then his playing style, goals, key moments. Then his celebrations as a way to engage fans. Discuss Conte's role in his success. Conclude with his legacy. Check word count. Let me outline each section with estimated words. Introduction: 100, Rise: 150, Playing Style: 150, Celebrations: 200, Conte's Role: 150, Legacy: 100. Total around 750. That fits the 600-900. Need to make sure the tone is factual but engaging. Avoid markdown, use only the allowed tags. No unsupported claims. Maybe mention specific matches where his celebrations were notable. Also, his move from Atletico Madrid to Chelsea and how that impacted his career. Wait, the user's context includes "The big Spanish striker notched 58 goals and made 120 appearances for the Blues over a three-and-a-half year spell at Stamford Bridge." So that's a key fact to include. Also, "Antonio Conte insane"—maybe Conte's tactical innovations, like the 3-4-3 system, which allowed Costa to thrive as a striker. That's a supported