I have understood that mandrakes are, if not useless so at least very hard to make good use of. However, how do you think they would work in a Kill Team list? (200 pts, every model work alone, no HQ or vehicles, at least 1 troops)
They are fast, can infiltrate and works good with cover, and each guy only needs to kill one model (with infiltrate and S4, shouldn't be too hard?) to get FnP and a pinning shooting attack. Something like this:
5 Mandrakes, Nightfiend - 85
10 Warriors, Dark Lance (good object holder while picking out enemies easy) - 115
or perhaps
5 Mandrakes - 75
10 Wyches, two with Hydra Gauntlets - 120
I'd like to try it out.