It solves the necessity to collect lots of money to spend on item upgrades, and adds a layer of progression that rewards the player. (thatvideogameblog.com)
One of the largest complications to the run is the fact that certain items upgrade in real time. (kotaku.com)
Kiwami «s item upgrade system is interesting and there are numerous items to collect — with clear «recipes» to create weapons and armour — but no real way to know where to find them. (stevivor.com)