If you aren't modding, the 1.06 update itself brought significant balancing changes noted by players on GameFAQs :
: Most major visual overhaul mods—including the Uncensored Mod and the Softman 2.0 Realistic SG mod—were designed specifically for 1.06. These mods often break or cause errors on later versions.
Feeding duplicates into your main weapon cards drastically increases your damage output and water tank capacity.