I've been trying to come up with a way to change player inertia only. My first try was to change friction in EntityEx.Head.vc . I changed friction values. It works for most part, but an unfortunate side effect is change in movement speed. Low friction allows player to move much faster, while high friction slows player down to a crawl. Any way around this ? If I only want to increase inertia, I guess I could fool around in EntityEx.Physics.vc and just cap player speed. But what if I want to eliminate inertia without affecting max speed ? Physics is not my strongest side, by the way.

High friction together with increased movement speed might do what you want.

I'm going to try that. Meanwhile, I've found something strange. According to ApplyFriction() in progs/common/linespec/EntityEx.Physics.vc, friction is not applied to airborne creatures. Then what makes flying player character gradually slow down once movement key is released ? If I understand correctly, on land with 0 friction creatures don't slow down unless they collide with something.

When player falls down it continues to move even after you release movement key. Flying with flight artifact has friction applied to player (check ApplyFriction).