Hey y'all i am relatively new but long story short i am gming for a agri-world(that consist's of many many islands and island continents with not an ocean but many rivers,lakes, and man made canals with roughly the temperature and climate of rural England) anyways the main enemies are dark eldar and......feral tyranids now here is the issue i need to figure out stats for the 'Nids now i know the mutations i am gonna give them( i am going to give them amphibious however i feel i should nerf their armor cause i am going to give them berserk to make them more dangerous boarders and beach landers) now while these ain't the only type of tyranid(theres are those weird mine-spore shooting things however they will be shooting landmines) also what would be a appropriate nerfing point for the amphibious tyranids, anyways they are a river patrol regiment from here( : https://community.fantasyflightgames.com/topic/177675-maritime-operations/ a really awesome resource)

also if it helps any this is a pdf(planetary defense force) regiment