Quicke Base [sm18_bear] is a great base level. The visuals are amazing for speedmapping, with a great attention to detail. The combat is also very tight. It's rather difficult with the enemy placement but definitely fair. Although it's a base map, it bends the rules a bit and throws in a couple fantasy enemies, which is how I like my base maps. Definitely worth playing. (My choice for best map of the pack)

sm18_blitz is a short linear slaughterfest of 16 enemies that leads into a pit out of the level. In other words, it's very unfinished. It even has a door at the start that says it's locked but has nothing behind it. There's also a part where you're forced to take some damage in toxic slime to get through the level. I'm unimpressed.

Act of Violence [sm18_miikka] is an overpopulated, packet overflow inflicting, basic architecture slaughterfest map. I didn't finish it but I don't think there's an exit to the map.

Castled [sm18_misyu] is a very good looking level with nice architecture and some great detail. The combat is also really good. It's not too difficult but not too easy. The silver key seems a bit pointless to me and a few parts of the map are a bit too dark, but apart from that, it's a very nice level that's worth a play.

sm18_nane is a boxy, short slaughterfest map where you round corners then shoot stuff. Rinse and repeat. There's a 3-Shambler fight at the end and one other kinda fun battle but overall it's not really worth playing in my opinion.