Good instrumental, but I think the first half is far more interesting than the second. 7/10
This song is definitely something I can go back to multiple times and not find it boring, at least for two thirds of it. The song starts off with something that sounds like a army marching into battle which is fitting considering the person this song is named after. After that, the song changes and becomes a very fast groove. This is probably my least favourite part of the song since it does nothing more than make me wonder how long they can keep up the groove and it feels much longer than what it really is, which makes the other parts feel short because they flow so well, compared to the fast section. The drumming is amazing during the entire song, though. Actually, this may be the best Clive Burr drum performance, in my opinion.
The song changes again with a very, very brief transition into my favourite part of the song. There's a sweeping majesty to this section and this one instead shows us what Genghis Khan has done in all of his glory (or dishonor). This section also foreshadows some upcoming songs, one of them being really, really popular with Iron Maiden fans. You probably know what song it is...
This song gets a 9/10 because how groovy it is.