Honoo no Mirage

Strong caring Male/Male relationships with drama and the supernatural? These are a perfect match...(although yami no matsui is a little bit fluffier fare) 

both are shounen-ai about a boy with mysterious powers, surrounded by supernatural enemies that meets a man that protects him since his past life.  

Same genres: Action, Adventure, Mystery, Historical, Supernatural, Drama. Although Honoo no Mirage is more tragic, but the series have similar plot elemets: reincarnation, spirits, clan wars, ambiguous but intense feelings between two main characters.  

Mirage of Blaze has more emotionally mature characters in it, like Ikoku..(aka A Foreign Love Affair). MofB is a strong drama, but Ikoku can compare to people who want different yaoi than the usual confused teen-age boys going at it. 

Mirage of Blaze is a unique anime that is similar to AnK but at the same time rather dynamically different. If you enjoy BL anime where the two main characters are constantly ‘clashing’ against each other and thus creating a sort of love/hate relationship with a huge dose of drama then give Mirage of Blaze a try. The relationship development in MoB is far more subtle than in AnK so take heed if you are not a fan of historical dramas and lack the patience to endure through a slow paced story. However MoB is worth watching, if you are unsure whether you will like it give it a try first.  read more 

BL in a dark context rather than what we typically see aka the kinda rough and deep type of BL both series are known for rather then within a typical slice of life or humourous setting. 

Both shounen-ai and supernatural. Both have older guy going for younger one. 

In both animes the characters find out that they are reincarnated spirits of people who died a long time ago, and their relations in the past affect their present life. There is yaoi in Mirage of Blaze and no yaoi in Nazca but the relations in Nazca are also very emotionally charged. 

'Eight Clouds' was giving me very strong MoB vibes right from the start. Both have a highschool student with special powers as main character, and coincidentally they look like twins. Both deal with Japanese mythology and/or history and both are pretty angsty. One exception - Eight Clouds is shoujo, while Mirage of Blaze is BL.  

they both have similar elements of supernatural, historical and action. 

Both are very serious, dramatic yaoi anime with a developed plot, strong passions and a deep conflict between main characters who are in love but cannot reconcile their differences. 

Both are rather similar in slashiness. Both have concepts of magic involved. Action/adventure levels are similar...Somewhat correspondingly have hints of romance.