SEGA announces a free update is coming to Total War: WARHAMMER II on December 14th, adding an experimental Skaven-themed sandbox mode called The Laboratory to the fantasy strategy sequel. They say this requires a powerful PC and offer a Laboratory FAQ to answer questions and a gameplay trailer to show things off. Here are more details:

Designed in collaboration with Intel® and aimed squarely at those with powerful gaming PCs, The Laboratory is a Skaven-themed Custom Battle playground. The Laboratory's numerous sliders allow multiple game variables to be tweaked, pushing battles in new and ridiculous directions. Players can massively ramp-up unit sizes, remove the bounds of gravity, and increase impact force tenfold to create scenes of pure chaos. With sixteen different settings to tinker with, players can even save their best combinations of tweaks to use again or share with friends.