Medic, although I also enjoy heavy and engineer. I live for team wipes with the kritzkrieg-it's my favourite medi gun. I exclusively play engineer in x10 unless the other team stacks battalions backup black box soldiers too much, in which case I switch to spy until those players leave. I play heavy because I am OK at it, but usually it's so our team composition is not terrible (pubs usually have stuff like 5x spy 5x sniper 1x f2p scout and then me)