Mordheim: City of the Damned

Go for this while playing with one warband for a year. Always try to level out your wyrdstone levels when making your required shipments. If you need the fragments, play missions with poor wyrdstone rating, if you need clusters, play missions with exceptional wyrdstone rating. By the time you get your warband rating around 2000, you will be able to hold your own against brutal/deadly ai. Just play very defensively and only pick up wyrdstone that is easy to get to. If you win the battle, you will pick up a decent amount of wyrdstone, so make sure you stay grouped up and focus on winning. When I unlocked this achievement I was maybe halfway through a year with one warband, so you have a lot of time to go for this achievement.