Wikipedia describes this:

The plot of Last Order encompasses two events that occurred before the main events of Final Fantasy VII. One storyline revolves around the Nibelheim scenario that focuses on Zack Fair, Cloud Strife, Sephiroth and Tifa Lockhart. The other event follows Zack and Cloud as they run from the megacorporation Shinra. The OVA cuts back and forth between these two flashbacks, linked by the narration of Turk leader Tseng and his reflections on the Nibelheim event. Originally meant to focus on Zack, Last Order highlighted Tseng’s feelings and position in the Shinra company, as well as his moral values.

May contain spoilers!

This OVA made by Madhouse studio and licensed by Square Enix. This anime directed by Morio Asaka and produced by Masao Maruyama, Jungo Maruta, Akio Ofuji; Tetsuya Nomura was the screenwriter. This OVA can be viewed in Japanese versions of the movie Advent Pieces: Limited, a special edition of Final Fantasy VII: Advent Children, and also for North America which is included in the bonus features of Final Fantasy VII: Advent Children Limited Edition Collector’s Set.

In this short OVA, fans of FFVII will witness the incident of Nibelheim and learn about the characters. If you played Final Fantasy VII or familiar with the story, you would know that the cause of the destruction of Nibelheim was none other than Sephiroth, a former hero and number one fighter in SOLDIER. I played the Crisis Core on the PSP and I was part of the action.

This anime makes a habit if switching scenes as we see both Zack and Cloud escape from Shinra and we get to observe Tseng and his mission to retrieve the escapee. Personally, I really this adaptation of this video game moment. I will be honest, I never played the actual game but only Dirge of Cerberus and Crisis Core and watched the movie Advent Children. Besides that, I think Madhouse studios really knows how to make the characters look serious and the atmosphere quite dark and suspenseful.  The anime is only in English Subbed but I thought the voices matched with the characters. Just listening to Sephiroth’s voice gives me the impression that he is both a violent but calm villain and Zack sounds like tough, cool guy. The fight scenes were handled well, especially between Zack and Sephiroth. Unless you played Crisis Core on the PSP, the fight would be extended. After I played Crisis Core, I did noticed that the OVA does skip through many parts of the story but since this was made before the game was made, I will make an exception. Also to add on it, the main focus I felt was solely on Tseng and the characters at Nibelheim.

I will not spoil the ending but it leaves a major cliffhanger. If you a fan of FFVII, you may know what happens next or if you were like me and played FFVII:CC, this gaming moment was painful to go through.

Overall, I really like this adaptation and I think it would be awesome to see an anime series or OVA series of Crisis Core. The fast pace story  and altered moments may be the negative points of the anime. I would recommend this to FFVII fans. Comment below on what you think about this OVA.